This paper examines future prospects for rainfed cereal production, and its importance in the evolving global food system. First, the paper undertakes a critical synthesis of the literature to assess three primary ways to enhance rainfed cereal yields: increasing effective rainfall use through improved water management, particularly water harvesting; increasing crop yields in rainfed areas through agricultural research; and reforming policies and increasing investments in rainfed areas. Second, the IMPACT-WATER integrated water-food modeling framework is applied to assess the current situation and plausible future options of irrigation water supply and food security, primarily on a global scale. This model simulates the relationships among water availability and demand, food supply and demand, international food prices, and trade at regional and global levels. The results show that rainfed agriculture will maintain an important role in the growth of food production in the future, although appropriate investments and policy reforms will be required to enhance the contribution of rainfed agriculture.