This study addressed what role movement timing irregularities have in producing the motor deficits documented in Asperger's Syndrome (AS). Participants included males with AS (n = 14) and without (n = 16), matched by age (7-23 years) and with no significant IQ differences. They completed measures of timing perception (comparisons of tempo of tones) and production (rhythmic finger tapping), and general motor skills (Dean-Woodcock Neuropsychological Battery motor tests). No central timing difficulties were noted, but the AS group showed more irregularity in motor implementation (with a large effect size), and this irregularity correlated with general motor skills.