The Checklist for Investigating Mechanisms in Behavior-change Research (CLIMBR) was developed under the SOBC initiative to aid both applied and basic behavioral scientists in their studies on the mechanisms of behavior change. CLIMBR offers a user-friendly checklist of guidelines to report the results of behavioral intervention development studies, to advance mechanism-focused science. CLIMBR is a powerful, standardized guide that uses a common method to enable the accumulation of behavioral science findings in a transparent and systematic way.