Supporting transformative adaptation and building equitable resilience to drought for sustainable development Achieving sustainable agricultural transformation is an international policy development priority. Growing high-value crops for export has been shown to generate substantive positive socio-economic impacts for the producing regions. The industry supports small-scale farmers and out-growers and provides secure employment and incomes for large numbers of people (especially women) in the primary production, packing and distribution sectors leading to higher and more stable revenues and positive impacts on the standard of workers' health, though better nutrition, access to appropriate food and education, whilst also providing greater job security. Increased smallholder agricultural production has also been shown to generate positive welfare effects and result in direct, as well as indirect, impacts on local livelihoods. The favourable climate and soils of many low and middle income countries (LMICs) opens opportunities to expand the export horticulture sector to meet the global demand for fruits and vegetables to support healthy diets.   Most export horticultural production in LMICs is irrigated and is increasingly moving into more arid areas and using water drawn from rivers, dams and aquifers that would otherwise be available for supporting natural habitats and environmental flows, underpinning smallholder agriculture and urban development, and for hydropower and industry. When the demand for water (from all sectors, including the environment) within a catchment, or from an aquifer, exceeds the available supply (hydrological drought) the impacts do not fall equally on all sectors due to power inequalities. For example, the economic and political power vested in the commercial horticultural sector may secure priority over water supplies; contractual obligations for produce for export may reduce availability and quality and increase prices in local markets; and low skilled workers in the horticultural sector may be laid-off when production falls. Thus the impacts on the poor and marginalised communities are exacerbated. Whilst drought is a natural occurrence, its frequency and magnitude are increasing due to climate change and increased water demand, particularly for domestic water and sanitation, and export horticulture will further exacerbate the vulnerability of poor and marginalised communities.   The challenge faced by many LMICs, has been how to support the expansion of the export horticultural sector to meet development objectives whilst increasing the resilience of poor and marginalised communities to drought and water-related risks, in the context of increasing climate variability.   Based on experience in case-study catchments, this project asks, 'how can the twin development objectives of a) increasing the resilience of poor and marginalised communities to drought and water related risks, and b) expanding commercial horticultural production in water-stressed catchments, be met in a socially and environmentally equitable manner?'   The proposed study is based on four case-study catchments in South Africa (SA) and Kenya (KE); The Breede Gouritz (Western Cape, SA), The Groot Letaba (Limpopo, SA), The upper Ewaso Ng'iro (Mount Kenya, KE), and Lake Naivasha (Nakuru, KE). These are all catchments with significant populations of rural poor that have been impacted by recent drought events; have important export horticulture industries; and include strategic water source areas. The Global Challenges Research Fund (GCRF) supports cutting-edge research to address challenges faced by developing countries. The fund addresses the UN sustainable development goals. It aims to maximise the impact of research and innovation to improve lives and opportunity in the developing world.