The purpose of this study was to describe the developmental stepping movements of 5 infants with Down syndrome who participated in a pediatric strength intervention. Pretest and posttest data were collected with the Hawaii Early Learning Profile Strands, Battelle Developmental Inventory, and specially designed gait analysis. An 8-week individualized pediatric strength intervention was implemented according to theoretical principles of progressive interactive facilitation (Cowden, in press). Posttest data and the Snyder-McLean intervention developmental quotient suggested an increase in the subjects' rates of motor development during intervention as compared to their lifetime rates prior to intervention. One subject showed increased rate and distance, 2 subjects acquired independent upright locomotion, and 1 subject established independent sitting movements and creeping patterns. One subject was unable to complete the study.