The National Primary Drinking Water Regulations were established on the premise that the source water would be relatively pollution-free and these standards were never intended to be comprehensive for determining the adequacy of the reuse of wastewaters for potable purposes. The purpose of this workshop was not to develop specific criteria and standards but to provide guidance with respect to approaches, problems, solutions and needed research or investigations for establishing a pathway to protocol development for potable reuse criteria and standards and for consideration of nonpotable options. The 'Report of Workshop Proceedings,' contains presentations by representatives from local, State, federal and international government agencies, consultants and universities. The first section includes introductory papers to outline the broad issues. The work groups were: Toxicology, Chemistry, Microbiology, Engineering, Ground Water Recharge, and Non-Potable Options.