This article presents results from a systematic review and two meta-analyses that examine whether prison yoga and meditation programs are significantly related to increased psychological well-being and improvements in the behavioural functioning of prisoners. Comprehensive searches of the empirical literature were conducted up to December 2014. Participants who completed yoga or meditation program in prison experienced a small increase in their psychological well-being (Cohen's d = 0.46, 95% confidence interval [CI] = [0.39, 0.54]) and a small improvement in their behavioural functioning (Cohen's d = 0.30, 95% CI = [0.20, 0.40]). Moderator analyses suggested that there was a significant difference in effect sizes for programs of longer duration and less intensity, compared with those that were shorter and more intensive, for psychological well-being. Programs of longer duration had a slightly larger positive effect on behavioural functioning ( d = 0.424), compared with more intensive programs ( d = 0.418). Overall, the evidence suggests that yoga and meditation have favourable effects on prisoners.