The emphasis is on those actively engaged in stream research rather than those who merely want to be kept abreast of developments in the field; individuals in the latter group will be maintained on a mailing list but not included in the Directory. The intent of the Directory is to increase communication between individuals working on stream problems. This is particularly necessary because of the very long delays between the submission and publication of stream research papers. The actively engaged in ecological research must now view the literature primarily as an historical record. Therefore, this Directory is offered in the hope that it will help insure that only useful duplication is a feature of contemporary stream research and that it will facilitate the continued identification of fruitful areas for investigation.