Using a modified Delphi process, we engaged 28 experts in clinical trials, geriatrics, and research translation to determine if there were consensus around what clinical endpoints should be used for trials evaluating the efficacy of interventions to prevent or treat multiple age-related conditions. Four focus groups developed themes. Statements related to those themes were circulated back to participants in a survey. There was consensus (more than 66% agreed or disagreed) that outcome measures should include multiple health dimensions including-age-related disease, function and patient reported outcomes that reflect participants goals; and be tailored to population characteristics. Experts felt that blood-based biomarkers would be unlikely to be accepted as primary endpoints of efficacy trials. Plausible components mentioned as part of a composite endpoint included mortality, mobility function and the onset of multiple age-related diseases. Our findings provide guidance on acceptable approaches to endpoint selection guiding the design of future geroscience trials.