Synopsis This book provides a brief description of the principles of biological nitrogen fixation, the different types of nitrogen-fixing plants, and the major potential uses of these plants to support agricultural development. ICIMOD's Demonstration and Training Centre at Godavari has a large collection of the type of nitrogen-fixing plants that are available to farmers in the mid-hills areas of the HKH region, and many of the ways in which they can be used in integrated farming approaches are demonstrated at the site. The book complements these activities and provides a basic introduction to the topic.