Community-based participatory research (CBPR) typically defines communities by geography, ethnicity, shared health needs, or some combination.We describe a CBPR project aiming to engage diverse minority and underserved communities throughout Michigan in deliberations about health research priorities.A steering committee (SC) with 15 members from minority and underserved communities and 4 members from research organizations led the project, with the help of regional advisory groups (RAGs) formed at the SC's request. Evaluation of the SC used questionnaires, focused group discussion, and review of SC meetings to describe engagement, partnership, and communication.An academic-community partnership with a diverse, dispersed, and broadly defined community found value in RAGs, dedicated academic staff, face-to-face meetings, varied communication modalities, capacity building tailored to varying levels of CBPR experience, and ongoing evaluation.A geographically and culturally diverse partnership presents challenges and opportunities in representativeness, relationship building, capacity building, and communication.