Objective: To assess the inclusion of patients as international research partners in Outcome Measures in Rheumatology (OMERACT) conferences and how this has influenced the scope and conduct of outcomes research in rheumatology. Design: A thematic content analysis of OMERACT internal documents, publications and conference proceedings, followed by a responsive evaluation including 32 qualitative semistructured interviews. Setting: The international, biannual research conference OMERACT 10 (Malaysia, 2010). Participants: Senior researchers (n= 10), junior researchers (n= 2), representatives of the pharmaceutical industry and regulators (n= 2), conference staff (n= 2), new patient delegates (n= 8) and experienced patient delegates (n= 8). Results: The role of patients evolved over 10 years from a single patient focus group to full participation in all areas of the meeting and inclusion in research group meetings between conferences. Five main categories of impact emerged: widening the research agenda; including patient relevant outcomes in core sets; enhancing patient reported instruments; changing the culture of OMERACT and consequences outside OMERACT. Patient participants identified previously neglected outcome domains such as fatigue, sleep disturbances and flares which prompted collaborative working on new programmes of research. Specific benefits and challenges for patients and professionals were identified, such as personal fulfilment, widening of research interests, difficulties in establishing equal partnerships and concerns about loss of research rigour. Conclusions: Including patients as partners in OMERACT conferences has widened its focus and adjusted the way of working. It has resulted in new developments in the research agenda and the use of more patient-relevant outcomes in clinical trials. These collaborations have influenced perceptions and beliefs among many patients and researchers, and led to wider patient involvement as partners in research.