While injuries are a leading health concern for Aboriginal populations, injury rates and types vary substantially across bands. The uniqueness of Aboriginal communities highlights the importance of collecting community-level injury surveillance data to assist with identifying local injury patterns, setting priorities for action and evaluating programs. Secwepemc First Nations communities in British Columbia, Canada, implemented the Injury Surveillance Project using the Aboriginal Community-Centered Injury Surveillance System. This paper presents findings from a community-based participatory process evaluation of the Injury Surveillance Project. Qualitative data collection methods were informed by OCAP (Ownership, Control, Access, and Possession) principles and included focus groups, interviews and document review. Results focused on lessons learned through the planning, implementation and management of the Injury Surveillance Project identifying lessons related to: project leadership and staff, training, project funding, initial project outcomes, and community readiness. Key findings included the central importance of a community-based and paced approach guided by OCAP principles, the key role of leadership and project champions, and the strongly collaborative relationships between the project communities. Findings may assist with successful implementation of community-based health surveillance in other settings and with other health issues and illustrate another path to self-determination for Aboriginal communities. The evaluation methods represent an example of a collaborative community-driven approach guided by OCAP principles necessary for work with Aboriginal communities.