The present study examines (a) the unique effects of chairwork on emotional process and intervention outcomes across treatments in the context of individual psychotherapy and (b) how these effects compare to other treatment interventions. Based on the appropriateness of the data available, meta-analyses with estimated effect sizes and narrative syntheses were conducted for psychotherapy process as well as symptom outcomes. Single-session chairwork was found to be more effective in deepening client experiencing than empathic responding (d = .90), although it may have an effectiveness similar to other interventions for facilitating emotional arousal or shifting the credibility of core beliefs. A single session of chairwork also has noteworthy pre-to-post symptom change (d = 1.73), although these improvements may be comparable to other methods of intervention (d = .02). However, when chairwork was used multiple times over the course of a treatment, it accumulated a meaningful effect (d = .40) compared to treatments that did not use chairwork. Therapeutic orientation emerged as a potential moderator. Incorporating chairwork into treatments may bolster process and intervention outcomes. We conclude the article with training implications and therapeutic practices. (PsycInfo Database Record (c) 2023 APA, all rights reserved).