Summary: In the wake of Africa's escalating food security crisis, marked by chronic undernourishment and stunted growth in children, a transformative approach to fertilizer use and soil health is paramount. Despite past efforts like the Abuja Declaration, fertilizer usage in Africa remains critically low, contributing to poor crop yields and persistent hunger. The recent African Fertilizer and Soil Health Summit has reignited hope with a comprehensive Action Plan aimed at integrating fertilizer use with sustainable soil health practices. This article delves into the necessity of deep and hyper-localization in policy and practice, advocating for tailored, evidence-based approaches to boost agricultural productivity. 12 is Professor in Michigan State University’s Department of Agricultural, Food, and Resource Economics (AFRE), Senior Co-Director of AFRE’s Food Security Group (FSG), and Director of the Feed the Future Innovation Lab for Food Security Policy Research, Capacity, and Influence (PRCI) funded by USAID  A cursory glance at the latest data on “Africa’s food and nutrition” reveals a grim reality: hundreds of millions are undernourished. According to the Food and Agriculture Organization (FAO), over 282 million Africans are chronically undernourished—a number exacerbated by the back-to-back effects of the COVID-19 pandemic and the Russia-Ukraine war, which have added tens of millions to this tally. The continent’s food security crisis is further underscored by the fact that over a billion people cannot afford a healthy diet, with children disproportionately affected; approximately 30% of African children are stunted due to malnutrition.  The fundamental driver of this crisis is the widespread poverty that makes so many unable to obtain the food they need, whether through their own production or through the market.  Yet there is no question that the continent's inadequate food production capabilities, and the failure of these capacities to keep up with population growth, is a major contributor to the crisis. A significant factor in this inadequate and slowing growing production capacity is low use of fertilizers and the poor health of soils across Africa. Compared to other regions, African countries use minimal amounts of fertilizer, resulting in lower crop yields and perpetuating cycles of hunger and malnutrition.   In recognition of this fact, and under the auspices of the African Union, the African continent just held a successful African Fertilizer and Soil Health Summit (AFSHS) in Nairobi.  Featuring wide attendance of political and food systems leaders across the continent together with development partners, the Summit captured and fueled their commitment and enthusiasm to improve the lives of African farmers and consumers.  A key contribution of the Summit was to harness this commitment to an Action Plan that provides a strong basis for addressing the continent’s longstanding agricultural productivity crisis.  A major reason that Summit participants emerged optimistic of progress is the specificity of the continental Action Plan and its understanding that fertilizer, if it is to drive sustainable intensification, must be integrated into a broad package of reformed policies and programs focused on soil health.   Yet we have been here before.  The Abuja Declaration on Fertilizer for the African Green Revolution, signed by 14 African heads of state and released during the African Fertilizer Summit of 2006, set lofty goals for increased fertilizer use and productivity growth on the continent.  Yet results have been disappointing at best.  On the one hand, fertilizer use per hectare (ha) of arable land has grown 79% since 2006, nearly double the growth rate of South Asia, comparable to the rate in Latin America and the Caribbean, and vastly higher than East Asia’s growth of only 8%. Yet this growth cannot be considered surprising since it started from an extremely low base; the result is that levels of fertilizer use in Sub-Saharan Africa today remain a small fraction of those in any other region of the world – 23 kg/ha compared to 207 kg/ha, 187 kg/ha, and 312 kg/ha, respectively, in Latin America and the Caribbean, South Asia, and East Asia (World Bank Databank). And use today is less than half the target of 50 kg/ha that the Abuja Declaration set for 2015.  Regarding productivity, while cereal yields nearly doubled from 2006 to now, this growth is less than half that achieved in every other region of the developing world during this time. This means that African agricultural productivity has fallen even further behind the rest of the world since Abuja.  The message is clear – Africa needed a big push to do major catch-up growth in fertilizer use, soil management, and yields, and failed to achieve it.  Partly as a result, after at least two decades of declining hunger and malnutrition, both have been on the rise on the continent in recent years.    What needs to be different this time?  A useful lesson in life and in work is that one should not expect different results while continuing to do what we’ve done in the past.  This lesson can be hard to learn, especially for the large bureaucracies – governments, large bilateral and multilateral development partners, and even the international agricultural research community - that are central to generating a productive response to the 2024 AFSHS.  So, what needs to change if we want, this time, to see the kind of transformational change that is needed in Africa’s agricultural production practices if the continent is to sustainably nourish its population and pull its people out of poverty?    This note suggests that obtaining different results this time – achieving sustained and effective action for improved fertilizer use and soil health - requires a much more profound localization of approach, and that this localization requires important changes in how governments, their development partners, and other stakeholders behave.  Specifically, we argue for two different but complementary approaches: deep localization in the process of policy and programmatic design and in how research to support that process is conceived and carried out; and what some call hyper localization in technical recommendations for farmer practices on their fields.  These two ideas – deep localization and hyper localization - need to be brought together to reinforce each other and jointly drive the design and implementation of a new and much more effective generation of policies and programs to achieve rapid and sustained growth in African agricultural productivity  The rest of this note explains what we mean by deep localization and hyper localization, why we believe that they need to go hand-in-hand in the follow-up to the AFSHS, and what they imply about how governments and development partners, including applied researchers in the global north and global south, need to change the attitudes and approach they bring to their work.   Hyper Localization  Hyper-localization is a popularized term that refers to the scientific concept of “4R” in soil nutrient management – right source, right rate, right time, and right place (Fixen, 2020; Reetz et al., 2015).  The messages is that one needs to apply the right kind of nutrient in the right formulation and needs to apply it at the right rate and at the appropriate time, based on the specific field receiving the nutrient.  Hyper-localization thus refers to the technical aspects of nutrient use and emphasizes customization to a farmer’s specific field. We offer four comments in this regard.  First, localized fertilizer recommendations are important across the world, since soil characteristics can vary quite a lot across countries, across regions in a country, across fields, and even within a field.  The rapid rise of “precision agriculture” in industrialized countries, in which a digital soil map of a farmer’s field linked to GPS technology that varies the blend applied by the machinery to match the soil map, is a clear indicator of the importance of highly localized fertilizer use to farmer profitability.  Second, much more localized application may be especially important in Africa, since this continent seems to present substantially higher variability over space in soil characteristics than other regions of the world (Suri and Udry, 2022).  Together with large variability over space in transport infrastructure, crop and fertilizer prices, and access to markets, this agroecological heterogeneity drives extremely large variation in returns to fertilizer (Suri, 2011).    Third, fertilizer policy in Africa has failed to come to terms with this heterogeneity through its decades-long “one-size-fits-all” approach.  Too often, a sharply limited set of fertilizer formulations is provided nationally, often through government programs at subsidized prices.  Given the heterogeneity just discussed, this is a recipe for poor profitability and low farmer adoption despite very high programmatic expenditures.    Fourth, implementing a 4R approach – enabling farmers to apply the fertilizer that their field needs, in the right amount and at the right time - requires that farmers have “access to knowledge, all needed fertilizers, and related services” (Reetz et al., 2015).  In other words, farmers need to know what to apply, they need to be able to get it, and they need to be able to access knowledge and inputs for complementary practices such as improved seeds and organic practices crucial to sustainable use of chemical fertilizers. We see two key reasons why all but a tiny fraction of farmers in Africa do not have this kind of access.  One is that, since at least the days of structural adjustment in the 1980s, African governments have dramatically under-invested in rural extension systems and in the soil testing and related agroecological profiling that would allow at least some evidence-based variation in fertilizer recommendations.  New technologies promise to reduce the cost of generating improved and spatially disaggregated knowledge of soil characteristics, but these need to be linked to functioning research and extension systems to be put to use for African farmers.    The second key reason that farmers don’t have this kind of access relates to fertilizer and broader agricultural input policy in much of Africa.  Private sector fertilizer distribution through markets in principle holds the prospect of providing farmers with greater choice in what they use, but national fertilizer policies frequently undermine these channels (Jayne et al., 2018).  Heavy reliance on imported formulations exacerbates this problem, though this is beginning to change due to a large increase in domestic blending of fertilizers.  The bottom line is that moving towards more localized fertilizer recommendations and practice is crucial if Africa’s productivity crisis is to be reversed, and requires greater public investment in data and data systems linked to strengthened rural extension, together with policy and programmatic reform to facilitate a flexible private sector response to farmer input needs.  Deep Localization and “nth-best solutions”  A recurring problem in Africa and many developing countries is the promotion of “showpiece” legislation and programs that mimic what outside experts consider “best practice” but that are never implemented (Pritchett, Wilcock, and Andrews, 2013).  Africa must avoid this in its follow-up to the AFSHS.  Rather than passively following outside advice, African countries need to marshal their own capacities and use their own processes, as imperfect as they may be, to develop action plans that are put into action, are able to appropriately evolve over time, and are informed by strong, local empirical evidence.  This can happen only through a deeply localized process in which stakeholders are engaged in an iterative process of analysis, design, dialogue, negotiation and bargaining, and redesign.  This process – indeed, development of workable policies and program in any country anywhere in the world – is an unavoidably messy social and political process.  Empirical scientific input is crucial to good outcomes but is not and cannot be the main driver of what emerges. Indeed, the outcomes that emerge, based on iterative dialogue and political compromise, are typically far from what a researcher would consider “best”.  We refer to them as “nth-best solutions”, meaning they are the best available solution given the technical, social, and political dynamics and constraints of the system one is operating in.  Far from failure, the development and implementation of such nth-best solutions is a sign of progress in a country’s ability to develop its own approaches that are feasible, “effective enough”, and can be maintained and improved over time.  Attitudes and behavior need to change  We have argued that the follow-up at country level to the AFSHS must involve deep localization, that is, a determination by local stakeholders simultaneously to seek out the best technical advice while subjecting it to the messy bargaining and “deal making” inherent in any authentic design of workable policies and programs that countries can own and take responsibility for. We have further argued that this follow-up must come to terms with Africa’s huge heterogeneity in agroecology, infrastructure, and market access, and generate an approach that allows for hyper localized solutions. These solutions will be possible only through recommendations that are more suitable to farmers’ particular fields combined with greater access by farmers to the knowledge, inputs, and services needed to pursue these recommendations while adapting them based on their own knowledge.  Achieving this will require simultaneously increasing public investment and reforming policies and programs to allow greater private sector response to farmer needs through functioning markets.  If African countries are able to do this, we believe they will generate policies and programs that, while far from what might be considered technically “best”, nonetheless stand a far greater chance of being implemented and adapted as needed, to impressive cumulative effect over time.  We suggest that attitudes and behavior by all parties will have to change to make this approach possible.  African governments will need to show keener interest in locally generated empirical information even as they promote a highly stakeholder-engaged process of policy and programmatic design that may generate outcomes far from what many consider technically best.  Local analysts need to understand and accept the fundamental social and political nature of this process while figuring out how to engage with that process and make their research understandable and relevant to decision makers.  The international research community must commit to working in equitable partnerships that involve giving up the right to drive the research agenda.  And donors need to recognize that things may take longer working this way and that countable and reportable outputs may be fewer but that outcomes – the changes that matter to people’s lives – should be greater.  Change is hard. Admitting that the way we as a global development community have approached empirically informed policy and programmatic change for many decades needs serious rethinking is especially hard.  But by focusing on equitable partnerships and accepting what, on any reasonable reflection, is so obvious – that policies and programs simply must adapt to local political and social realities even while striving to be as effective and efficient and equitable as possible – this change is possible.  We know how to proceed – let’s get on with it!    References  Liverpool-Tasie, LSO, B. Omonona, A. Sanou, W. Ogunleye,   (2015). “Is Increasing Inorganic Fertilizer Use in Sub-Saharan Africa a Profitable Proposition? Evidence from Nigeria”.  Food Policy, 67, 41-51.  https://doi.org/10.1016/j.foodpol.2016.09.011.  Burke, W., T.S. Jayne, J.R. 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