BACKGROUND: Crowdsourcing methods have been widely used in business, but rarely in sexual health research. We evaluated a crowdsourced logo contest as part of an international human immunodeficiency virus conference. METHODS: A logo crowdsourcing contest was conducted for the 20th International Acquired Immunodeficiency Syndrome Conference. Crowdsourcing has a group of individuals solve a task, often as part of an open contest. Semistructured interviews were conducted with key informants including contest organizers, contest contributors, and conference attendees. Interviews were transcribed verbatim and analysed using a content analysis approach. RESULTS: In total, 22 interviews were conducted with 3 contest organizers, 7 contest contributors, and 12 conference attendees. All individuals reported that the crowdsourced logo provided benefits beyond branding the conference, including creating a shared sense of purpose among diverse conference participants and explicitly demonstrating the strong community orientation of the conference. Conference organizers and attendees all reported deeper engagement because of the story of the Tanzanian artist who won the contest. Most conference attendees (11/12) preferred the crowdsourced logo compared with the previous company-organized logo, and all (22/22) supported the logo contest continuing. Implementing a logo contest was simple and relatively inexpensive. Stakeholders identified several ways to enhance crowdsourcing logo contest methods including wider promotion of the contest to encourage broader participation, greater transparency in the selection process, and a different prize structure which acknowledges the contribution of more contestants. CONCLUSIONS: We found that a crowdsourcing contest helped engage local and global communities in the lead-up before and during an international conference. Similar participatory events may be useful for sexual health conferences and research projects.