Drought stress is one of the most deleterious environmental factors responsible for severely limiting the growth and productivity of agricultural crops. The expected long-term effects of global climate change include more frequent episodes of drought. This book presents current research in the study of droughts including the response of plants to drought stress; the physiological and molecular bases of drought tolerance in wheat genotypes; the spatial assessment of drought hazard, vulnerability and risk in Bangladesh; the influence of drought and forest fires on the productivity of evergreen oaks in the Iberian Peninsula and developing drought tolerant crops.