To examine the effectiveness of group circuit class therapy for improving the mobility of adults after stroke. Cochrane systematic review. A comprehensive search strategy was used to find randomized and quasi-randomized controlled trials of adults post-stroke receiving circuit class therapy. Two authors independently selected trials for inclusion, assessed the methodological rigor and extracted data. Six trials were included, involving 292 participants; most were community-dwelling survivors who were able to walk independently. Circuit class therapy was effective in improving walking ability (6-minute walk test mean difference, 76.6 m, 95% confidence interval 38.4-114.7, walking speed mean difference 0.12 m/s, 95% confidence interval 0-0.24) and balance (step test mean difference 3.0 steps, 95% confidence interval 0.08-5.9, activities specific balance confidence mean difference 7.76 points, 95% confidence interval 0.66-14.9). Other balance measures did not show a difference in effect. Results from two studies suggest that circuit class therapy can reduce length of hospital stay (mean difference -19.7 days, 95% confidence interval -35.4 to -4.0). Two studies measured adverse events (falls); all were minor. Circuit class therapy is safe and effective in improving mobility in people after stroke and, when provided as part of hospital-based rehabilitation, may reduce length of stay.