Background and Purpose - Overground gait training can be defined as a physical therapists' observation and cueing of the patient's walking pattern along with related exercises, but does not include high-technology aids such as functional electric stimulation or body weight support. This systematic review investigated the effects of overground physical therapy gait training on walking ability for chronic stroke patients with mobility deficits. Methods - A comprehensive literature search was performed as per the Cochrane group guidelines. Only randomized controlled trials that compared overground physical therapy gait training to a placebo intervention or no treatment for chronic stroke patients with mobility deficits were included. Results - Nine studies involving 499 participants matched the inclusion criteria and had moderate methodological quality. Results were mixed with no significant effect on the primary variable, gait function. Small effects for several performance variables were found: gait speed increased by 0.07 meters per second (95% confidence interval [CI] = 0.05 to 0.10) based on 7 studies with 396 participants, timed up-and-go (TUG) test improved by 1.81 seconds (95% CI = -2.29 to -1.33) based on 3 studies and 118 participants, and 6-minute-walk test (6MWT) increased by 26.06 meters (95% CI = 7.14 to 44.97) based on 4 studies with 181 participants. No significant differences in adverse events were found. Conclusions - There is insufficient evidence to determine whether overground gait training directly benefits broad measures of gait function. Results from recent studies, however, suggest that specific training protocols may provide limited benefits for more uni-dimensional performance variables like gait speed, TUG test, and 6MWT. (Stroke. 2009; 40: e627-e628.)