This paper recounts experiences, challenges, and lessons learned when implementing a lay patient navigator program to improve cancer care among medically underserved patients who presented in a primary care clinic with a breast or colorectal cancer abnormality. The program employed five lay navigators to navigate 588 patients. Central programmatic elements were the following: (1) use of bilingual lay navigators with familiarity of communities they served; (2) provision of training, education, and supportive activities; (3) multidisciplinary clinical oversight that factored in caseload intensity; and (4) well-developed partnerships with community clinics and social service entities. Deconstruction of healthcare system information was fundamental to navigation processes. We conclude that a lay model of navigation is well suited to assist patients through complex healthcare systems; however, a stepped care model that includes both lay and professional navigation may be optimal to help patients across the entire continuum.