This article explores the fundamental role that strong community partnerships play in successful recruitment and retention of program participants; prevention program implementation; program sustainability; and institutionalization of prevention strategies throughout the community. Our study revolves around the community engagement process that provided the foundation for the successful implementation of an adolescent pregnancy prevention program in a predominantly minority, low-income community. The community has long had high teen birth rates and a history of fragmented, short-lived partnerships with outside organizations. But the study found that a deliberate approach that uses a well-planned, well-executed strategy to build on existing community assets and partnerships, as well as create new ones, is a key factor in successful program implementation. This article identifies core principles and strategies that support strong community partnerships and specific engagement techniques that build, maintain, and sustain these vital relationships. Finally, it presents a broader model of community change that comes from the strong engagement of multiple partners. The information shared is intended to assist programs and their sponsoring organizations in achieving greater success in developing and nurturing strong relationships with individual community members, as well as stakeholders and gatekeepers in schools, civic organizations, the faith community, businesses, and other health and human services.