Soil fertility reflects the physical, chemical and biological state of soil and soil fertility can be defined in relation to the plants that grow naturally or are introduced into soil. This book contains chapters on various aspects of soil fertility which are meant for training of extension workers in soil fertility management techniques and for workers involved in rural development that would like to learn more about the principles and practices of ISFM. This book is also a useful primer on ISFM for education organizations such as universities and technical colleges, organizations involved in the development of policy on agriculture and rural development that need reference materials on ISFM techniques, and other government and non-government organizations (NGOs) seeking to implement ISFM.