Integrating the voices of service users and providers in the design and delivery of health services increases the acceptability, relevance, and effectiveness of services. Such efforts are particularly important for youth opioid use treatments and services, which have failed to consider the unique needs of youth and families. Applying community-based participatory research (CBPR) and co-design can facilitate this process by contextualizing service user experiences at individual and community levels and supporting the collaborative design of innovative solutions for improving care. However, few studies demonstrate how to effectively integrate these methods and engage underserved populations in co-design. As such, this manuscript describes how our team wove CBPR and co-design methods to develop solutions for improving youth opioid use treatments and services in Canada. As per CBPR methods, national, provincial, and community partnerships were established to inform and support the project's activities. These partnerships were integral for recruiting service users (i.e., youth and caregivers) and service providers to co-design prototypes and support local testing and implementation.

Co-design methods enabled understanding of the needs and experiences of youth, caregivers, and service providers, resulting in meaningful community-specific innovations. We used several engagement methods during the co-design process, including regular working group meetings, small group discussions, individual interviews and consultations, and feedback grids. Challenges involved the time commitment and resources needed for co-design, which were exacerbated by the COVID-19 pandemic and limited our ability to engage a diverse sample of youth and caregivers in the process. Strengths of the study included youth and caregiver involvement in the co-design process, which centered around their lived experiences; the therapeutic aspect of the process for participants; and the development of innovations that were accepted by design partners.