This joint study has two objectives: to analyze the historical climate trends in the region, identify hotspots and determine the potential implications for livelihoods which depend on natural resources; and to provide recommendations for improving conflict and migration sensitivity in adaptation planning, investments and policies across the region. The study, which covers 17 countries in the Sahel and West Africa, was released on 5 December 2011. Using an innovative mapping process to analyze trends in temperature, rainfall, drought and flooding over the past 40 years, this report provides an important contribution to policy-makers and practitioners seeking to ground adaptation policies and investments in a sound understanding of the nature and scale of historical climate trends in the Sahel, and their impacts on livelihoods.