Nowadays, water as a human life necessity, not only plays a major role in the life cycle of living beings but also is considered as an essential factor for the economic and social development of any region. The book has been written on "Stochastic Modeling for Reference Crop Evapotranspiration" This book fulfills the needs of the agricultural/horticulture/water resources studies /farmers, research scholar, students of agricultural and agricultural engineering, studying in different institutions of the country. It could also be useful to Scientist, farmers and professional working in this field. The book covers information regarding the importance of reference crop evapotranspiration methods and forecasting of evapotranspiration for water management studies. The knowledge of water requirement is necessary to match the spatial and temporal distribution of water demand with water supply for efficient utilization of water resources. Evapotranspiration is a major component of water requirement. Evapotranspiration varies according to the crops, their growth stages, crop condition, soil parameters and climate.