The association between physical growth and gross motor development, particularly self-produced locomotion, was considered in 557 children 3-18 months of age. Gross motor development was assessed with nine preselected milestones representing the major landmarks in self-produced bipedal locomotion. Motor development is presented by age and by milestone, and is compared to developmental ranges of the Denver Developmental Screening Test. Consistent with other studies of undernutrition and motor development, length-for-age, but not weight-for-length, was a significant predictor of gross motor development (i.e., delayed or not delayed). The effect of weight-for-age on motor development was not statistically significant after accounting for length-for-age. © 1994 Wiley-Liss, Inc.