This book focuses on proving that deficit irrigation could play an important role in increasing food production in times of water scarcity. Although the application of deficit irrigation can involve loss in crop productivity, it still secures water to be use in cultivating more lands and producing more food. The following questions are discussed and the authors offer solutions to these problems: Will the production, on a national level, resulting from these new added areas compensate yield losses attained by application of deficit irrigation? Is it possible to use deficit irrigation practice to reduce the applied irrigation water to certain crops that have a surplus in their production, and direct this saved water to cultivate new areas with crops have low self-sufficiency ratios? Under climate change in 2030, would deficit irrigation practice have the same role it plays under the current conditions? This book will appeal to students and researchers involved with water scarcity and food security.