1. Concept of Evaporation and Transpiration 2. Water use of crop 3. Factors affecting evapotranspiration 4. Concept of reference crop evapotranspiration (ETo) 5. Crop evapotranspiration under standard conditions (ETc) 6. Crop evapotranspiration under non-standard conditions (ETc adj) 7. Calculation of reference evapotranspiration, ETo 8. Kc and crop 9. α value method for ETc calculation