The aim of this study was to assess the effectiveness of mindfulness-based interventions (MBIs) for reducing psychological distress in working adults. A comprehensive literature search of relevant databases included articles written in English published on December 2012. The meta-analysis included 19 controlled and uncontrolled intervention studies with a total of 1,139 participants. Analyses yielded medium-to-large mean effect sizes for the within-group (pre–post) comparison (Hedges's g = 0.68, 95 % confidence interval (CI) [0.58, 0.78]) and for the between-group (Hedges's g = 0.68, 95 % CI [0.48, 0.88]) comparison of MBI with an inactive control. Effectiveness was largely maintained at a median follow-up of 5 weeks (Hedges's g = 0.60, 95 % CI [0.46, 0.75]). Analyses based on subgroup comparisons suggested that brief versions of mindfulness-based stress reduction developed for organisational settings are equally effective as standard 8-week versions originally developed for clinical settings. However, there is little evidence to suggest that MBIs are more effective than other types of occupational stress management interventions, such as relaxation training and yoga, for reducing psychological distress in working adults. Overall, these findings support the use of MBIs in organisational settings for the reduction of psychological distress. Implications for practice and research are discussed.