The purpose of this article was to present the current state of evidence and experience of youth participation approaches in HIV and sexual and reproductive health decision-making, policies and programmes. By combining a literature review of evaluation evidence with in-depth interviews and a global survey targeting young people with the experience of participation, this study opens a new window into the support needs for meaningful youth participation globally. Limited available evidence indicates that youth participation has positive effects on programme, self-efficacy and empowerment outcomes for the young people engaged in policies and programmes. Young people who have participated in decision-making reflected on improvements in outreach and representation of young members of key affected populations, but also expressed concerns about tokenism, age-based hierarchies and access for younger adolescents, women and marginalized groups. Overall, evidence indicates a need for further investments in capacity building, training, inclusive participation spaces and research on meaningful youth participation.