This report captures the key principles of sustainable irrigation at the farm scale. And is an update including recent research. The NPSI Knowledge Harvest brings together information from across the National Program for Sustainable Irrigation (NPSI) projects, highlighting key findings and promoting wider understanding. Key Harvest themes: Irrigation Overview - facts, figures and key concepts about irrigation. Water Delivery Systems - the efficient storage and distribution of water for irrigation. On-farm Irrigation Essentials - principles for efficient irrigation. Recycled Water - recycling treated effluent and stormwater for irrigation