Despite well-documented benefits of physical activity for cancer survivors, few interventions have been developed for Native American cancer survivors, the population with the poorest survival rates of any group. This paper describes the development and cultural adaptation of a physical activity intervention for Navajo cancer survivors using Intervention Mapping (IM). IM procedures were guided by the PEN-3 (Perceptions-Enablers-Nurturers) and Health Belief Models and informed by a qualitative study with 40 Navajo cancer survivors and family members. For each theoretical construct (perceived benefits, barriers, enablers of healthy behaviors, etc.), a measurable objective was identified. These objectives were then matched with intervention strategies. The IM process indicated the need for a highly culturally sensitive environment (site and providers), culturally acceptable measurements and materials, and integrating cultural and environmental activity preferences. Program objectives aligned directly with these areas. Intervention strategies included: (a) collaboration with providers sensitive to historical/cultural context and environmental barriers; (b) cultural adaptation of surveys, non-invasive physical measurements, no biospecimen storage; (c) materials, terminology and symbols embracing cultural values of return to harmony; (d) physical activities that are flexible and aligned with cultural preferences and environment/travel issues (e.g., outdoor walking; community and homebased options; portable, inexpensive resistance equipment; local resources; family/friends participation and more community cancer education); (e) clinical adaptations by site and symptoms. This study is the first to document the process of adaptation of a physical activity program for Navajo cancer survivors. Objectives and strategies incorporated via IM are expected to foster sustainability and enhance uptake, satisfaction, and adherence.