As service-learning is adopted by growing numbers of higher education institutions, there is increasing interest in understanding the factors necessary to sustain service-learning for the long-term. Institutions that were early adopters of service-learning may offer important insights into what factors influence long-term sustainability. With this aim in mind, we conducted a retrospective, qualitative study of the ten-year sustainability of service-learning among a cohort of sixteen colleges and universities that participated in a national demonstration program of service-learning from 1995 to 1998. We assessed the extent to which service-learning was sustained at each institution, and explored the factors that influenced sustainability, including facilitators, challenges, and strategies for success. (Contains 6 notes and 2 tables.)