Mental health research projects address sensitive issues for vulnerable populations and are implemented in complex environments. Community-Based Participatory Research approaches are recommended for health research on vulnerable populations, but little is known about how variation in participation affects outcomes of partnered research projects. We developed a conceptual model demonstrating the impact of community engagement in research on outcomes of partnered projects. We collected data on key constructs from community and academic leaders of 21 sampled partnered research projects in two cycles of an NIMH research center. We conducted empirical analyses to test the model. Our findings suggest that community engagement in research is positively associated with perceived professional development, as well as political and community impact.