This study used a multivariate approach to assess anaerobic power in 20 athletes and 20 nonathletes undergoing 6 weeks of plyometric training, and 20 controls. A 3 X 2 mixed model MANOVA was done to analyze the pre- and posttest scores of vertical jump, 50-m dash, and Margaria-Kalamen stairclimbing test. The Group X Test interaction was significant (p < 0.001). Both groups that underwent plyometric training improved significantly (p < 0.01) on all tests of anaerobic power. Of the dependent measures, the Margaria-Kalamen test was the most influential in the development of a multivariate composite of anaerobic power. It appears that plyometrics is effective for increasing lower body anaerobic power for both athletes and nonathletes, and the Margaria-Kalamen stairclimbing test is a better tool for assessing this power than either the vertical jump or the 50-m dash. © 1997 National Strength & Conditioning Association.