Patient navigation (PN) is increasingly used in cancer care, but little is known about the identification and training of patient navigators. PN may be implemented by professional health care providers, paraprofessionals, or lay health workers and, therefore, presents an opportunity to compare professional and lay interventionist experiences. The goal of the current report is to compare the training experiences of four professional (Pro) and five lay (LHW) patient navigators enlisted to increase colonoscopy adherence among African American primary care patients. The results of early assessments showed that LHWs' intervention-related knowledge was significantly lower than that of Pros. However, there were no significant differences in knowledge scores between LHWs and Pros for most subsets of knowledge items in later assessments. Furthermore, there were no significant differences in LHWs' and Pros' reported self-efficacy and satisfaction with training. Findings support the use of diverse strategies to train and prepare LHWs as patient navigators.