Background <p>While there is growing inclusion of people who use drugs in research and policy forums, they are typically excluded when program outcome indicators are determined. We discuss the methods, results, and lessons learned from two projects that engaged people who use drugs, who are living with or at risk of HIV, and service providers in collaborative outcome indicator development.</p> Methods <p>Project 1 was conducted with stakeholders of a future day health program and project 2 with stakeholders of safer opioid supply program. For both projects, we included (1) capacity building about the definition and measurement of outcome indicators with stakeholders; (2) collection of stakeholder perspectives about important outcome indicators; (3) rating/selecting proposed outcome indicators; and (4) analyzing and disseminating findings regarding recommended outcomes. We collected and analysed all suggested outcome indicators using content analysis techniques. As a team, we reflected on the lessons learned from our projects.</p> Results <p>For study 1, we recruited <i>n</i> = 18 clients who participated in up to 4 sessions, and 10 staff/clinicians and 3 leadership members who participated in one session each. For study 2, 8 program clients, 7 internal program providers, and 8 external agency service providers participated in one session each. During the sessions in both projects, participants were shown the mandated outcome indicators for the respective programs, and each group emphasized the need to measure social outcomes in addition to health outcomes, with clients in both studies preferring qualitative interviews for collecting outcome data .Domains of outcome indicators which were highlighted in study 1 include quality of life; mental health; satisfaction with pain management; access to harm reduction services; social connectedness; and ease of readmission for those with frequent episodic illnesses. For study 2, the highlighted outcome domains included experiences of social isolation and connectedness, experiences of discrimination in health and service setting, changes in self-care and leisure activities, and experiences of grief and loss.</p> Conclusions <p>Our experiences demonstrate the value of an interactive, participant-driven approach to outcome indicator development that integrates capacity-building to foster meaningful engagement. Across both projects, clients, staff, and leadership contributed valuable insights that enhanced future program evaluation, with participants generating practical, inclusive indicators—some of which were incorporated into electronic medical records and outcome surveys to better capture client well-being. We also identified important lessons about session structure and virtual engagement, finding that condensed sessions can increase accessibility and diversity of input, while virtual formats offer new opportunities for inclusion, but require additional support to engage structurally vulnerable participants meaningfully.</p>