Two experiments examined whether video game expertise transfers to performance on measures of spatial ability. In Experiment 1, skilled Tetris players outperformed non-Tetris players on mental rotation of shapes that were either identical to or very similar to Tetris shapes, but not on other tests of spatial ability. The pattern of performance on those mental rotation tasks revealed that skilled Tetris Players used the same mental rotation procedures as non-Tetris players, but when Tetris shapes were used, they executed them more quickly. In Experiment 2, non-Tetris players who received 12 hours of Tetris-playing experience did not differ from matched control students in pretest-to-posttest gains on tests of spatial ability. However, Tetris-experienced participants were more likely to use an alternative type of mental rotation for Tetris shapes than were Tetris-inexperienced participants. The results suggest that spatial expertise is highly domain-specific and does not transfer broadly to other domains. Copyright © 2002 John Wiley & Sons, Ltd.