It is often claimed that Expert Systems ( ES) can profitably be used in developing countries whe re the number of trained professionals in any field is relatively small. This paper gives a brief description of the field of medicine in the Tanzanian context, provides a brief theoretical analysis of an ES, proposes some of the requirements which need to be met in developing an ES suitable for rural based health care delivery on the basis of a recent survey, and examines how Expert Systems could help to support and expand the existing structures providing medical and related care as. well as indicating the advantages of ESs. The paper also looks at the problems and conditions which may limit the application of Expert Systems in health services in Tanzania and other developing countries.