There is no clear evidence to guide mental health professionals in assessing and treating angry clients. Recent reviews have considered cognitive and behavioral approaches to the treatment of anger, but little is known about the potential effectiveness of other treatment modalities. A meta-analytic review was conducted to examine the effects of treating dimensions of anger by using various psychological treatments found in the scientific literature. The final analysis included 96 studies and 139 treatment effects. The nine types of psychological treatments included cognitive, cognitive behavior therapy, exposure, psychodynamic, psychoeducational, relaxation-based, skills-based, stress inoculation, and multicomponent. The overall weighted standardized mean difference across all treatments was 0.76 (95% confidence interval [CI], 0.67-0.85, Q = 403.13, df 138, p < .001, I(2) = 65.76), which suggests that psychological treatments are generally effective in treating anger. The results also suggest a considerable degree of variability in the effect sizes of specific treatments for anger. The results show that at least some of the variability may be explained by the number of treatment sessions offered to participants, the use of manuals to guide delivery of the treatment, the use of fidelity checks, the setting of the research, and whether the study was published or unpublished. This review builds on previous evidence of the effectiveness of psychological treatments of maladaptive anger, and it provides the basis for developing evidence-based guidelines for specific populations with anger problems.