OBJECTIVE: This is an update from the Outcome Measures in Rheumatology (OMERACT) Core Outcomes in Longterm Observational Studies Special Interest Group with a focus on rheumatoid arthritis. METHODS: Preliminary data and proposed next steps were outlined and discussed by participants. RESULTS: Domains identified after initial steps (systematic review and qualitative research) were pain, physical functioning, participation (i.e., work, social), longterm symptoms, fertility/family planning, emotional well-being, coping, financial status, and adverse events including death. CONCLUSION: The group agreed conceptually that short-term core outcomes could be different from longer term ones. Participants emphasized the importance of analyzing the need for core domains specifically for longterm longitudinal observational studies.