This paper describes one component of the Study of Dissemination Efforts Supporting School Improvement, which focused on the role that external facilitators play in helping schools implement new educational practices. The first part describes the external facilitator sample (95 respondents) and delineates the major formal role groups of external facilitators included in the sample: state facilitators, developer/demonstrators, and Title I developer/demonstrators, all from the National Diffusion Network; school-based developer/demonstrators engaged in locally developed projects (with ESEA Title IV-C funding); and state-administered developer/demonstrators. A brief discussion ensues concerning respondents' perceptions of their initial contact with schools. This is followed by a description of the kinds of assistance external facilitators gave to the schools, categorized according to the five stages of the adoption/implementation process: (1) intiating relationships, (2) assisting clients in deciding on new practices, (3) assisting clients in preparing for adoption, (4) assisting clients in implementing practices, and (5) followup activities. The last section concerns the effects of external agent assistance on local site outcomes in individually focused and school-focused models developed in the study. (TE)