The purpose of this paper is to describe the development and implementation of community-based, service-learning field projects by 30 health professional faculty fellows of Project MAINSTREAM, a faculty development program on substance abuse. The fellows worked together for two years in 10 Interdisciplinary Faculty Learning Groups (IFLGs), which consisted of three academics of different disciplines. The ten projects are viewed within the context of service- learning and are based on a balance between the provision of services to the community and furthering the learning objectives of Project MAINSTREAM.