This Food Policy Report presents the results of a study that quantifies the impacts of climate change mentioned above, assesses the consequences for food security, and estimates the amount of investments that would offset the negative consequences of climate change on human welfare. This analysis brings together for the first time, the detailed modeling of crop growth under climate change with insights from an extremely detailed global agriculture model, using two scenarios to simulate future climate. The results of the analysis suggest that climate change will negatively affect agriculture and human welfare: In developing countries, climate change will reduce the performance of the most important crops. South Asia will be particularly affected. Climate change will have different effects on the yields of irrigated crops in all regions, but crops will diminish significantly in South Asia.