PURPOSE: Less than 10% of patients enrolled in clinical trials are minorities. The patient navigation model has been used to improve access to medical care but has not been evaluated as a tool to increase the participation of minorities in clinical trials. The Increasing Minority Participation in Clinical Trials project used patient navigators (PNs) to enhance the recruitment of African Americans for and their retention in therapeutic cancer clinical trials in a National Cancer Institute-designated comprehensive cancer center. METHODS: Lay individuals were hired and trained to serve as PNs for clinical trials. African American patients potentially eligible for clinical trials were identified through chart review or referrals by clinic nurses, physicians, and social workers. PNs provided two levels of services: education about clinical trials and tailored support for patients who enrolled in clinical trials. RESULTS: Between 2007 and 2014, 424 African American patients with cancer were referred to the Increasing Minority Participation in Clinical Trials project. Of those eligible for a clinical trial (N = 378), 304 (80.4%) enrolled in a trial and 272 (72%) consented to receive patient navigation support. Of those receiving patient navigation support, 74.5% completed the trial, compared with 37.5% of those not receiving patient navigation support. The difference in retention rates between the two groups was statistically significant (P < .001). Participation of African Americans in therapeutic cancer clinical trials increased from 9% to 16%. CONCLUSION: Patient navigation for clinical trials successfully retained African Americans in therapeutic trials compared with non-patient navigation trial participation. The model holds promise as a strategy to reduce disparities in cancer clinical trial participation. Future studies should evaluate it with racial/ethnic minorities across cancer centers.