The results of a study are presented, using both literature surveys and interviews (with resource persons who had personal field-experiences), on successful or less successful interactions between indigenous knowledge systems and formal knowledge systems in the context of forest management. It is suggested that there is a far wider potential for indigenous knowledge than is currently applied or integrated in projects and programmes. The study was conducted from September 1997-April 1998. Illustrative case studies are drawn from a variety of developing countries: Nepal, Kenya, Bolivia, Laos, Colombia, Mali, Madagascar, Ecuador, Ethiopia, Solomon Islands. Nine discursive chapters examine: concepts and analytical framework; indigenous forest-related knowledge; value of and threats to indigenous forest-related knowledge; aspects requiring special attention during project identification; aspects for attention during project formulation and implementation; the role and position of extension and training; dealing with local authorities; and tools to preserve and enhance indigenous knowledge.