Patryk Kugiel, Henriette U. Erstad, Morten Bøås, Jolanta Szymańska
While the EU’s hardened policy on irregular migration has led to a drastic reduction in the number of arrivals to Europe since 2015, the global migration pressure is not abating. In 2019, the number of international migrants was estimated to be almost 272 million (or 3.5% of the world’s population), with nearly two-thirds being labour migrants. This included almost 26 million refugees in 2018, the highest since the Second World War. Migration flows are only expected to increase in the coming decades, driven by a wide range of factors such as poverty, demographic imbalances, and climate change. In Africa alone, the population is expected to double by 2050, simultaneously with a rise in poverty, resource scarcity, and violent conflict.
To avoid a repeat of the dramatic events of 2014–2015, migration management in the “neighbourhood” has, therefore, become a top priority for the EU and European governments. An important dimension of their approach has been to address the “root causes” of irregular migration through development assistance for migrant-sending and transit countries. Whether this policy is fit for purpose is, however, a question that remains unanswered. The aim of this paper is, therefore, to review the existing literature on the development-migration nexus with a focus on European responses to suggest possible directions for future research. Overall, it argues that the “root causes approach” is questionable in light of the empirical evidence. Moreover, in order to design more fine-tuned and knowledge-based policies, future research needs to better address the great variety that exists among migrants and the different countries they come from or transit through.
Development and Migration—a Complex Relationship
The migration-development nexus is at the epicentre of the “addressing root causes” approach, here defined as “the totality of mechanisms through which migration and development dynamics affect each other.” While the relationship between these mechanisms is complex and far from straightforward, policymakers often find it intuitive that aid can stir development, and more development therefore will lead to less migration. The logic is that donors can help eradicate poverty, create jobs and enhance economic development in poor countries, and thus, eliminate the main reasons why people decide to emigrate. Naturally, it is also argued that when refugees are given enough humanitarian assistance in their countries of origin or third countries, they are not forced into “secondary movements.” In short, it is better to help migrants in their home countries (or close to them) rather than face the pressure of irregular migration in Europe. Yet, such a causal link (i.e., development reduces migration) is questioned by researchers who find the relationship between development assistance and migration both complex and far from obvious.
In general, to better understand the migration-development nexus (although it varies by context), it is important to look closer at three crucial relationships in the existing literature: between aid and economic development, development and migration, and the role of migration in the development of origin countries.
First, it is still debatable how much of an impact traditional development cooperation has on economic growth in receiving countries. One reason for this is that aid is only one of many external interventions (together with, for example, trade, foreign direct investment, remittances, transfer of technologies) that can help countries grow. Therefore, the literature criticising development assistance and its impact on the Global South is rich and expanding. Yet, international efforts since 2000 aimed at realising the Millennium Development Goals have substantially contributed to halving extreme poverty, limiting deaths of children, and sending more kids to schools. There is also evidence showing a positive impact of aid on economic development, provided it is big enough and sustained over a long period of time. For instance, Clemens et al found that the provision of aid at levels of 10% of the GDP of a receiving economy could raise its growth by 1 percentage point (p.p.) per year. Nevertheless, for a country to experience positive aid effects, this will depend on a wide range of other factors such as administrative absorption capacity, legitimate and transparent institutions, trust, political stability, and human capital. Increased aid in itself is simply not enough.
Second, and perhaps most surprising, is the counterintuitive relationship between development and migration. Several studies show that more development in the poorest countries (especially the Least-Developed Countries) will lead to more, not less migration, at least until a country reaches a certain level of economic prosperity. Simply put, when people get richer, they have more capacity to finance expensive migration. Moreover, their aspirations grow much faster in relation to the improvement of the macroeconomic situation in their own countries, fuelling desires to realise their potential elsewhere. Some studies have also shown that it is not necessarily the poorest and the least educated who migrate to Europe irregularly. It is not a coincidence that almost none of the Nigerian migrants that reach Europe are on the run from the Boko Haram conflict in Northern Nigeria as the massive flows of Internally Displaced Persons (IDPs) and refugees that this conflict has created are simply too poor and lack the networks needed to have any chance of reaching Europe. They are stuck as IDPs in their own countries or as refugees across the border in the Diffa region of Niger.
As a result, providing aid could, in fact, fuel migration in the short-to-medium term rather than reduce it. Indeed, one of the most important studies in the field indicates that both bilateral aid and recipient’s total aid have significantly positive impacts on migrant stocks. According to some scholars, the relationship is neutral at best. Similarly, recent major studies “find no evidence that aid reduces worldwide refugee outflows or flows to donor countries in the short term.” Yet, it is important to recognise the many theoretical and methodological challenges related to measuring migration aspirations.
Though we witnessed a renewed interest in the development-migration nexus following the 2015 crisis, it has been under scrutiny since the 1960s. It was, for example, observed that with the rise of GDP per capita, emigration from poor countries must first rise before it can eventually fall: Zielinski called it the “mobility transition” and presented it as an inverted-U. Since then, many scholars found a similar pattern and gave it different names, like “migration curve,” “migration transition,” “emigration life cycle,” and “migration hump.” Scholars have long debated what constitutes the tipping point when it comes to migration and GDP per capita—and if there is one. Some studies have argued that only after reaching PPP $6,000–$8,000 per capita income, higher incomes are associated with reduced emigration, while others gave the exact amount at about $7,300 per capita in PPP 2000 prices, or located this closer to PPP $8,000–$10,000. That would mean, as calculated by some, that if today’s poorest countries continue to grow at their historical growth rate (over the last 24 years), they would only reach PPP $8,000 in the year 2198.
Nevertheless, GDP per capita is not necessarily a suitable indicator—economic growth may, for example, say more about the elites than the population as a whole. Indeed, if economic growth isn’t inclusive and trust-building, it might even more strongly contribute to an increase in migrant aspirations. Moreover, it is not fully understood whether objective levels of development are enough to comprehend the migration decisions of individuals or one needs to take more seriously the relative level of development (in relation to neighbouring countries or to the richest parts of the world) and an individual’s sense of deprivation and marginalisation. It is important to note in this regard that in 2013–2017, the average income in high-income OECD countries was $43,083, compared with just $795 in low-income countries, a staggering ratio of 54:1. Moreover, while global poverty is decreasing, intraregional inequality is increasing. For example, both poverty and inequality are rising in Sub-Saharan Africa, which is also the region where one finds the world’s most fragile states and the youngest population. Here, it is not unreasonable to argue that push factors for migration to Europe will persist for the foreseeable future.
Indeed, there are dimensions other than the economic situation of a home country that also largely influence emigration decisions. This can include macro-level factors such as existing migrant networks, demographic trends, geographical and historical links, level of security, climate change, and micro-level factors such as age, sex, individual skills, and education, perception of available opportunities abroad, trust in government institutions, and risk management.
Another crucial category for our understanding of migration decisions is the relationship between “aspiration” and “ability” to migrate. Research on “migration aspiration” underlines the importance of psychological or social drivers of migration. As one recent global analysis of intentions to migrate suggests, migration is strongly linked to aspiration (for a better life, economic opportunities and development of skills) than desperation or the experience of poverty. It is found that “being young, male, foreign-born, highly educated, unemployed, or having networks abroad are all strongly associated with a higher likelihood of preparing for international migration.”
Migration decisions are highly contextual and can differ from region to region, country to country, and individual to individual. It is interesting to ask how increased access to information and decreased costs of migration can affect the traditional development-migration patterns? With technological, demographic, and economic changes, will the same relationship observed in the past between development and migration continue in the future? Thus, more studies focused on local conditions and drivers of migration are required.
The third question about migration’s impact on development leads to less controversy today. Though in the past, the relationship was seen as largely negative in terms of depleting crucial human capital in home countries (referred to as “brain drain”), since the new millennium, most researchers underline a more positive impact. Migration most often brings benefits not only to an individual but also to his/her family and home country, as it leads to a transfer of financial resources and skills. Positive effects of migration on the eradication of poverty and economic growth is possible through sending remittances, engagement of diasporas in stimulating development of their countries of origin, the role of returning migrants in transfers of technology and skills, impacts on trade between destination and origin country, and the transfer of non-financial resources (social, cultural, and political). It is enough to remember that remittances sent back to low- and middle-income countries (LMICs) by migrants in 2019 were expected to reach $551 billion—three time more than total ODA and on track to overtake for the first time foreign direct investment (FDI) flows to LMICs.
Overall, the positive impact of migration on development has been widely acknowledged internationally and is reflected in the Sustainable Development Goals (especially target 10.7) of the new Agenda 2030, adopted in 2015, and underlined in the Global Compact for Migration signed by 164 countries in late 2018. Moreover, there is an emerging consensus that migration—if properly managed and controlled—can have positive effects on destination countries as well. Even more surprisingly there are emerging studies showing that an inflow of refugees “may also bring economic opportunities and positively contribute to the development” of host countries. As UN Secretary-General António Guterres stressed: “migration is a positive global phenomenon” that “powers economic growth, reduces inequalities, connects diverse societies and helps us ride the demographic waves of population growth and decline.”
Yet, some scholars urge caution against taking too optimistic a view of the role of migration in enhancing growth and seeing migrants as agents of development. Hans de Hass observed that “migrants alone can generally not remove more structural development constraints and migration may actually contribute to development stagnation and reinforce the political status quo.” In fact, a recent study on 11 European states showed that “most of the countries’ policies still reflect an understanding of migration as a problem and a preoccupation with short‐term domestic interests.”
Moreover, there are many theoretical and methodological challenges that need to be considered when investigating the migration-development nexus. First and foremost, a shortcoming in the existing literature is the lack of conceptual clarification. It is, for example, essential to better differentiate between the forced displacement of refugees and the mobility of economic migrants, which obviously requires different responses. The refugees fleeing conflicts, persecution, or natural disasters need different assistance than those motivated to migrate abroad voluntarily. While most attention and political tensions in Europe in recent years were caused by the refugee-management crisis, it is economic migration that in the long term poses a greater challenge for Europe. Yet, it is not always easy to distinguish between the two groups in times of “mixed migration” when a person can be both a refugee and a voluntary migrant in different stages of his/her migration. It is even more important to examine the mutual interaction between refugees and migrants, for instance, how the inflow of refugees can affect migration patterns in a host country or how the local situation can impact secondary movements of refugees.
In addition to this, the great variety that exists between countries of origin and transit countries is also rarely addressed. Sending countries, for example, vary between those that are poor (i.e., Bangladesh), illiberal (i.e., Eritrea), and fragile and/or conflict-affected (i.e., Nigeria). In a similar vein, transit countries can be poor (i.e., Morocco), illiberal (i.e., Turkey), and fragile and/or conflict-affected (i.e., Niger). This becomes even more complicated when we have to account for the fact that some states are both sending and transit countries, with Turkey and Niger being illustrative examples. These distinctions must be considered in order to design and implement more context-sensitive and fine-tuned research and policy advice to better manage irregular migration.
Table 1. Examples of Different Types of Migrant-Sending and Transit Countries
Fragile and/or conflict-affected
Critique of the “Root Causes” of Migration Approach
In light of the existing literature, it is not surprising that politicians’ views diverge with that of scholars and practitioners. The European “root causes” approach to migration is increasingly criticised by experts, NGOs, and partner countries. There are several possible shortcomings or risks in using aid to achieve migration goals.
First, using aid for migration-related goals can have a possible negative impact on aid quality. Though total ODA amounts rose sharply in 2015 and 2016 in response to the refugee-management crisis, this was largely a result of increased spending to cover the costs of hosting refugees in donor countries. As this money did not reach developing countries, NGOs consider it “inflated aid” (together with debt relief, tied aid, or student costs). For instance, this category accounted for 20% of total ODA reported by the EU in 2016 (€15.40 billion), an increase of 43% compared to 2015. Out of this a total, €10.88 billion was spent on refugees—one in seven euros reported by the EU donors as aid. For instance, 38% of Austria’s aid budget went to cover the costs of hosting refugees on its own territory; in Italy, it was 34.3%; and, in Germany, 25.2%. Recent calculations show that although inflated aid decreased in 2018 (as fewer refugees are reaching EU Member States), still 14% of European aid was the inflated type, the equivalent of more than €9.9 billion, down from 18.5% in 2017. Inflated aid allows donors to fulfil their ODA commitments without real improvement of people in the Global South. It may thus undermine EU commitments to finance the SDGs and eradicate poverty, in line with its international obligations.
Another concern related to the decreased quality of aid is reduced transparency of migration-related aid. New European trust funds were created to allow for greater flexibility, but at the same time, they have escaped closer oversight and scrutiny in terms of management and effectiveness. This makes monitoring of aid money as well as research and evaluation of migration-related ODA more difficult.
Most importantly, using aid as a tool for curbing migration means that the EU may undermine the needs of partner countries and thus, aid effectiveness principles, especially local ownership and alignment of aid with partners’ development priorities. As recent reports by European NGOs warn: “the focus on migration management promoted by several EU Member States carries severe risks of diverting financing from priorities vital for reducing poverty while strengthening EU relations with governments who violate human rights and repress their citizens.” They criticise the trend in EU policy, also in the context of the negotiations of the next Multiannual Financial Framework, to condition ODA on the cooperation of countries on migration issues.
The second risk of the “root causes” approach is the possible collateral damage to partner countries. The diversion of European aid from the traditional focus on the eradication of poverty to migration concerns may lead to negative, even if unintended, consequences for developing countries and migrants themselves. For instance, the EU Emergency Trust Fund for Africa (EUTF) in the Sahel induces adverse effects in terms of development, human rights and migration. Some authors point out that securitisation of Niger’s borders, pushed by the EU, has “reduced the political and economic benefits of intra-regional migration,” left the local economy and population that relied on cross-border activities with no alternative source of livelihood and more vulnerable, and that this policy forced migrants to seek new, more dangerous migration routes to Libya. As a result, “the EU’s deployment of development aid for humanitarian purposes seeks to solve the problem that it has partly created.” Moreover, human rights groups warn that the EU bears some responsibility for human-rights violations committed in migration detention camps in Libya. Other critics hold the EU accountable for the increasing number of drownings in the Mediterranean Sea.
Above all, an important pitfall of aid delivery in fragile states to deter irregular migration is related to “the fragility dilemma,” which manifests itself in two ultimately interconnected ways. On the one hand, these states are in desperate need of international assistance while simultaneously being the most difficult to assist. They are less predictable, more volatile, and highly vulnerable to changing conditions. As their institutional and administrative capacity is low, the level of traditional donor aid that can be effectively absorbed is limited. Until recent years, therefore, the international development community has avoided engagement in such settings due to the likelihood of tangible results being low. As a consequence, traditional donors have limited experience and know-how when it comes to the fragile states that have suddenly been thrust on top of the international development agenda due to concerns related to mass migration (and terrorism). Moreover, the new security-development agenda, which the EU’s external migration policies cannot be seen in isolation of, may put fragile states on international life support. While this may prevent state collapse in the short term, it fails to foster sustainable processes of stabilisation and developmental state-building.
On the other hand, the fragility dilemma means that power hierarchies and dynamics are not always what they seem in fragile states. Usually, the regime in power is well aware that the country has become a top priority, as it is: (i) located in relatively close proximity to Europe; and (ii) an area where irregular migrants come from or transit through. Moreover, external actors are highly dependent on the regime as they see no real alternative. As a result, donors may be cautious of insisting too heavily, and with too much conditionality, on reforms that the regime in power has little interest in and may even see as a threat to its own survival. This fragility dilemma is therefore important to recognise when designing and implementing external migration policies in weak and fragile states.
And finally, using development assistance to prevent migration may also lead to a backlash against aid. Though “root causes” rhetoric worked well initially for mobilising support for increasing financing for ODA, it may not last long. Once the general public in Europe realises that the relationship between development and migration is actually positive (more aid means more migration) they may turn against foreign assistance spending. It could feed anti-migration and populist forces across the Member States, further constraining the ability for a more active EU role in international affairs. Already, as one study in a country that took the largest number of refugees shows, “development aid is not an effective tool to comfort immigration critics.” Therefore, more honest and evidence-based narratives about the role of aid in migration may be needed.
Overall, the current “root causes approach” puts development policy in tension with migration policy. It also discloses an internal contradiction or paradox in EU development cooperation, observed already a decade ago. If the EU’s development cooperation stated objective is the “reduction of poverty” (see Art. 208 TFEU), aid shall facilitate migration rather than reduce it since migration has been proven to be a powerful tool in fighting poverty. If aid focuses on stopping migration, it contradicts its main goal. Moreover, while meant to address root causes, this approach is, in reality, a short-term plan to manage migration flows rather than to promote development in the long-term.
Does Development Assistance Reduce Migration?
The existing literature has, however, also outlined three areas where the positive impact of development assistance on migration can be seen. First, in the most obvious dimension, ODA has been used as an incentive or leverage (one may even say as a bribe) to extract closer cooperation from partner countries in migration management through stricter border controls and signing agreements on return and readmissions. Though this approach may be politically sensitive (often dealing with non-democratic regimes) and morally dubious (i.e., cooperation with Libyan militias), in the short-run it has proved quite successful. Turkey, in exchange for €6 billion in aid blocked the flow of refugees (mostly Syrians) to Europe through the Eastern Mediterranean route since 2016. Sahel countries, given millions of euros from the EUTF for Africa, tightened border controls to disrupt main migration routes from Sub-Saharan Africa. And since February 2017, the EU has been increasing cooperation with Libya to reduce irregular immigration, providing the country with €237 million to fund programmes addressing migration challenges, which includes assistance to Libyan border guards and running detention camps for migrants intercepted at sea. Such instrumentalisation of aid has played a crucial role in the “externalisation” of migration policy.
Second, more recent literature has revisited traditional knowledge about the development-migration nexus and points at more “optimistic” findings. For instance, Lanati and Thiele, by using a substantially extended and adjusted econometric approach based on a gravity model of international migration and taking migrant flows rather than migrant stocks as the dependent variable, found evidence of a negative relationship between total aid a country receives and emigration rates. Their research shows that intervention in particular sectors are more effective than in others, as aid affects migration decisions differently depending on whether it effectively raises household incomes or improves public services. They claim that if assistance helps to upgrade nonmonetary dimensions of wellbeing (like healthcare, quality of education, governance) it tends to reduce emigration. Governance, health, and education also represent so-called trust-building sectors, which implies that investing in these areas can help restore trust in government as well. Such investments can be more effective in addressing root causes than more traditional development assistance (i.e., leading to income growth or better economic infrastructure).
Similarly, Gamso and Yuldashev found that aid aimed at improving governance (promoting better institutions, less corruption, and more political stability) reduces migration, while aid for economic and social development neither positively nor negatively affects migration rates. This may sound like good news to politicians keen to use aid as a tool in migration management, but they need to realise that actually getting aid to work as a trust-building mechanism in poor and fragile states will be immensely difficult, as the recent experiences from countries such as Afghanistan and Mali suggest. Another study by the same authors points out that aid to rural areas is negatively associated with emigration rates, whereas there is no significant relationship between aid to urban areas and migration. Conversely, investments in skills development, education, vocational training, and business development programmes may raise aspirations and incomes, often leading to increased migration, especially when the local market is not sufficient to satisfy these aspirations and existing networks ease emigration. These recent studies point to the need to move away from the macro-analysis of relations between GDP growth and migration and instead focus more on research at the micro-level and particular sectors.
Third, there is no denying that humanitarian aid brings positive effects and is crucial for the survival of displaced persons, and may prevent the need for their secondary movement if their needs are adequately met. Moreover, there is consensus that aid can strengthen the resilience of developing nations and help reduce migration over a longer term. This is because often the positive effects of interventions in social and economic infrastructure can only be seen after many years. Moreover, while aid should not seek to stop migration, it can help regulate and manage migration in a more effective way. Therefore, many argue to focus on finding synergies between development cooperation and migration rather than using the former to deter the latter. To put it simply, migration is development. As one scholar suggests: “there is enough evidence now for [...] policymakers to move beyond development instead of migration policies.” In this sense, aid could be used in order to promote “circular migration,” reduce remittance costs, enhance intraregional worker flow, or help train workers in need in an ageing Europe.
Conclusions: A Framework for Future Research
While irregular migration to Europe seems to be back under control at the moment, the long-term migration pressure is here to stay. Hence, there is a mounting need for effective instruments and policies to better manage international mobility and make it work for all. Development cooperation seems to be one key tool the EU has in external relations, but it needs to reflect on its potential in light of existing knowledge on the development-migration nexus.
A good place to start is to acknowledge that the “root causes” approach to migration is questionable in light of empirical evidence, as several studies show a positive causal relationship between development and migration. It also raises serious risks in terms of aid quality, popular support to foreign assistance and unintended consequences for developing countries. It is not to say, however, that aid has no role in better managing migration or tackling some of its “root causes.” As more recent studies point out, aid to specific sectors can actually decrease migration flows. It suggests that the questions are not “if” but “how” can aid help in dealing with this challenge.
Further research is therefore needed in this field in order to better understand the impact of aid on individual migration decisions and, thus, provide knowledge-based advice to policymakers on how to politically manage irregular migration flows. The politicians should be well informed about what is realistically possible to achieve through development aid in terms of migration so their communication with the electorate does not create unrealistic or misguided expectations. If European states want to use ODA to ease migration pressures, they must know what forms of aid can bring more positive effects and what forms may risk doing the opposite.
There is a gap especially in contextual analyses that take a more comprehensive view (not only focused on income) of the drivers and triggers of migration. One needs to pay more attention, for instance, to the aspirational aspect of human mobility and in this context examine whether assistance can indeed help to create an attractive alternative to migration, and what forms of intervention (i.e., to improve public services, better governance or increase income) would improve the most citizens’ satisfaction in their home countries.
Future research must factor in the great variety between the different types of sending and transit countries, and between forced and voluntary forms of mobility. One needs to comprehend better specific forms of assistance directed to all distinctive groups, but also complex interactions between these groups and actors. Another crucial task is to assess the “fragility dilemma” in dealing with the most vulnerable states.
More studies from either the countries where most migrants come to Europe from or the ones they transit through that host their biggest number would be helpful to understand the development-migration nexus better. There is a great chance to prove that even if aid can’t stop migration, it could certainly help harness its potential for the mutual benefit of migrants and sending and hosting countries alike.
The publication is prepared in the framework of initiative: Migration and Development: Sharing knowledge between Poland and Norway (MiDeShare). The Initiative is funded by Iceland, Liechtenstein and Norway through the EEA Grants and Norway Grants.
Working together for a green, competitive and inclusive Europe.
 See: Frontex, “Number of Irregular Crossings at Europe’s Borders at Lowest Levels in 5 years,” Frontex, 4 January 2019, https://frontex.europa.eu/media-centre/news-release/number-of-irregular-crossings-at-europe-s-borders-at-lowest-level-in-5-years-ZfkoRu.
 “World Migration Report 2020,” International Organisation for Migration, Geneva, 2019, p. 2.
 World Bank, “Leveraging Economic Migration for Development. A briefing for the World Bank Board,” World Bank Group, Washington DC, September, 2019, p. XVI.
 M. Tempest, “Africa’s Population Set to Double by 2050, Says New Report,” Euractiv, 26 August 2016, https://www.euractiv.com/section/development-policy/news/africas-population-set-to-double-by-2050-says-new-report/.
 M.A. Clemens, H.M. Postel, “Deterring Emigration with Foreign Aid: An Overview of Evidence from Low-Income Countries,” CGD Policy Paper 119, Center for Global Development, Washington, DC, 2018; M. Siegel, “Throwing Development Money at the ‘Migration Problem’—is it Completely Misguided?,” MIGNEX Blog, 2019, https://www.mignex.org/publications/throwing-development-money-migration-problem-it-completely-misguided.
 J. Carling, “Thirty-Six Migration Nexuses, and Counting,” 2017, https://jorgencarling.org/2017/07/31/thirty-six-migration-nexuses-and-counting/. The concept of the migration-development nexus was initially introduced in N.N. Sørensen, N. Van Hear, P.E. Pedersen, “The Migration-Development Nexus: Evidence and Policy Options,” International Migration, vol. 40, no. 5, 2002, pp. 49–73.
 See also: L. Andersson, M. Siegel, “Empirical Assessments of the Development Impacts of Migration,” MIGNEX Background Paper, Peace Research Institute Oslo, 2019, www.mignex.org/d024.
 See: W. Easterly, The White Man’s Burden: Why the West’s Efforts to Aid the Rest Have Done So Much Ill and So Little Good, Oxford University Press, 2006; D. Moyo, Dead Aid: Why Aid Is Not Working and How There Is a Better Way for Africa, New York: Farrar, Straus and Giraux, 2009.
 M.A. Clemens, S. Radelet, R.R. Bhavnani, S. Bazzi, “Counting Chickens When They Hatch: Timing and the Effects of Aid on Growth,” Economic Journal, vol. 122, no. 561, 2012, pp. 590–617.
 J. Berthélemy, C., Beuran, M. Maurel, “Aid and Migration: Substitutes or Complements?,” World Development, vol. 37, no. 10, 2009, pp. 1589–1599; M.A. Clemens, “Does Development Reduce Migration?,” Working Paper, Center for Global Development, Washington DC, 2014, p. 359; M.A. Clemens, “Development Aid to Deter Migration will do Nothing of the Kind,” Refugees Deeply, 31 October 2016; UNESCO, “Migration as Development Challenge. Analysis of Root Causes and Policy Implications,” MOST, January 2017; H. Temprano Arroyo, “Using EU Aid to address the Root Causes of Migration and Refugee Flows,” Migration Policy Centre, European University Institute, Florence, 2019.
 UNDP, “Scaling Fences: Voices of Irregular African Migrants to Europe,” UNDP Report, 21 October 2019.
 J.C. Berthélemy, M. Beuran, M. Maurel, “Aid and Migration: Substitutes or Complements?,” World Development, vol. 37, no. 10, 2009, pp. 1589–1599.
 H. de Haas, “Turning the Tide? Why Development Will Not Stop Migration,” Development and Change, vol. 38, no. 5, 2007, pp. 819–841; M. Murat, “Foreign Aid and Responsiveness of Bilateral Refugee Inflows,” Working Paper 130, Recent Center for Economic Research, University of Modena and Reggio Emilia, 2017.
 A. Dreher, A. Fuchs, A. and S. Langlotz, “The Effects of Foreign Aid on Refugee Flows,” European Economic Review, 112, 2018, pp. 127–147.
 J. Carling, “Measuring Migration Aspirations and Related Concepts,” MIGNEX Background Paper, Peace Research Institute Oslo, 2019, www.mignex.org.
 W. Zelinsky, “The Hypothesis of the Mobility Transition,” Geographical Review, vol. 61, no. 2, 1971, pp. 219–249.
 S. Akerman, “Theories and Methods of Migration Research,” in: H. Runblom, H. Norman (eds.), From Sweden to America: a History of the Migration, Minneapolis: University of Minnesota Press, 1976, pp. 19–75.
 J.D. Gould, “European Inter-Continental Emigration 1815–1914: Patterns and Causes,” Journal of European Economic History, vol. 8, no. 3, 1979, pp. 593–679.
 T.J. Hatton, J. G. Williamson, “What Drove the Mass Migrations from Europe in the Late Nineteenth Century?,” Population and Development Review, vol. 20, no. 3, 1994, pp. 533–559.
 P.L. Martin, J. E. Taylor, “The Anatomy of a Migration Hump,” in: J. Edward Taylor (ed.), Development Strategy, Employment, and Migration: Insights from Models, Paris: Organization for Economic Cooperation and Development, 1996, pp. 43–62.
 Purchasing Power Parity (PPP).
 M.A. Clemens, 2014, op. cit., p. 6.
 J.C. Berthélemy, M. Beuran, M. Maurel, 2009, op. cit.
 M.A. Clemens, H.M. Postel, “Deterring Emigration with Foreign Aid; an Overview of Evidence from Low-Income Countries,” CGD Policy Paper 119, February 2018.
 M.A. Clemens, 2014, op. cit., p. 6.
 See: M. Czaika, H. de Haas, “The Role of Internal and International Relative Deprivation in Global Migration,” Oxford Development Studies, vol. 40, no. 4, 2012, pp. 423–442; P. Bhandari, “Relative Deprivation and Migration in an Agricultural Setting of Nepal,” Population and Environment, vol. 25, no. 5, 2004, pp. 475–499.
 World Bank, 2019, op. cit., p. XVII.
 M. Latek, “Interlinks between Migration and Development,” Briefing, European Parliamentary Research service, 2019, pp. 4–5.
 J. Carling, “Migration in the Age of Involuntary Immobility,” Journal of Ethnic and Migration Studies, vol. 28, no. 1, 2002, pp. 5–42.
 See: J. Carling, F. Collins, “Aspiration, Desire and Drivers of Migration,” Journal of Ethnic and Migration Studies, vol. 44, no. 6, 2018, pp. 909–926.
 S. Migali, M. Scipioni, A Global Analysis of Intentions to Migrate, European Commission, JRC111207, 2018.
 N.N. Sørensen, N. Van Hear, P. Engberg‐Pedersen, “The Migration–Development Nexus: Evidence and Policy Options,” International Migration, vol. 40, no. 5, 2002, pp. 3–73.
 “Data release: Remittances to low- and middle-income countries on track to reach $551 billion in 2019 and $597 billion by 2021,” World Bank blogs, 16 October 2019.
 See: IOM, “World Migration Report 2018,” International Organisation for Migration, Geneva, 2017; FAO, “Addressing the Root Causes of Migration and Harnessing its Potential for Development 2016,” Food and Agriculture Organisation, Rome, 2016.
 “Making migration work for all. Report of the Secretary-General,” UN General Assembly, 17 December 2017.
 See.: D. Khoudour, L. Andersson, “Assessing the contribution of refugees to the development of their host countries,” OECD, Paris, 28 September 2017.
 “Secretary-General’s remarks at launch of Report ‘Making Migration Work for All’,” UNGS, 11 January 2018.
 R. Skeldon, “International Migration as a Tool in Development Policy: a Passing Phase?,” Population and Development Review, vol. 34, no. 1, 2008, pp. 1–18; H. de Haas, “The Migration and Development Pendulum: a Critical View on Research and Policy,” International Migration, vol. 50 no. 3, 2012, pp. 8–25.
 Ibidem, p. 8.
 N. Keijzer, J. Heraud, M. Frankenhaeuser, “Theory and Practice? A Comparative Analysis of Migration and Development Policies in Eleven European Countries and the European Commission,” International Migration, vol. 54, no. 2, 2016, p. 69.
 “CONCORD AidWatch 2019—EU Aid Uncovered: How to Reach the Target on Time,” CONCORD Europe, Brussels, 2017, p. 6.
 Ibidem, p. 15.
 “CONCORD AidWatch 2019—Leaving no one behind: Time for implementation,” CONCORD Europe, Brussels, 2019, p. 10.
 “CONCORD Aid Watch 2019—EU Aid Uncovered…,” op. cit., p. 15.
 Ibidem, p. 18.
 M. Latek, op. cit., p. 10.
 S. Fine, S. Dennison, R. Gowan, “False Moves: Migration and Development Aid,” Policy Brief, European Council on Foreign Relations, October 2019, p. 9.
 “No Escape from Hell. EU Policies Contribute to Abuse of Migrants in Libya,” Human Rights Watch, 2019.
 S. Fine, “All at Sea: Europe’s Crisis of Solidarity on Migration,” Policy Brief, European Council on Foreign Relations, October 2019.
 M. Bøås, “Fragile States as the New Development Agenda?,” Forum for Development Studies, vol. 44, no. 1, 2017, pp. 149–154.
 S. Schneider, J. Eger, E. Ademmer, D. Hudson, J. van Heerde-Hudson, T. Stöhr, “Comforting Immigration Critics? Public Opinion toward Development Aid as a Tool to Reduce Refugee Inflows to Germany,” MEDAM Policy Brief 2019/1, 2019.
 O. Bakewell, “Keeping Them in Their Place: The Ambivalent Relationship between Development and Migration in Africa,” Third World Quarterly, vol. 29, no. 7, 2008, pp. 1341–1358.
 D. Boffey, “Migrants Detained in Libya for Profit, Leaked EU Report Reveals,” The Guardian, 20 November 2019.
 See, for example: R. Carayol, “What Happened When the EU Moved its Fight to Stop Migration to Niger,” The Nation, 5 July 2019, www.thenation.com; A. Lebovich, “Halting Ambition: EU Migration and Security Policy in the Sahel,” EU Council on Foreign Relations, 25 September 2018, www.ecfr.eu.
 M. Lanati, R. Thiele, “The Impact of Foreign Aid on Migration Revisited,” World Development, 111, 2018, pp. 59–74.
 J. Gamso, F. Yuldashev, “Targeted Foreign Aid and International Migration: Is Development-Promotion an Effective Migration Policy?,” International Studies Quarterly, 2018, pp. 1–12.
 J. Gamso, F. Yuldashev, “Does Rural Development Aid Reduce International Migration?,” World Development, 110, 2018, pp. 268–282.
 M. Lanati, R. Thiele, op. cit.
 P.D. Sutherland, “Migration is Development: How Migration Matters to the Post-2015 Debate,” Migration and Development, vol. 2, no. 2, 2013, pp. 151–156.
 M.A. Clemens, “Does Development…,” 2014, op. cit., p. 29.