Kinematic data were collected on two groups of children with diagnoses of idiopathic toe-walking and mild spastic diplegia. Although both groups lacked a heel strike at initial contact, two distinct gait patterns were found. The toe-walkers displayed a variable pattern of ankle motion with moderate to severe plantarflexion at stance. The cerebral palsy patients showed a repeatable gait pattern with only minimal deviation from normal. The absence of a heel strike in this group is due to the sustained knee flexion at terminal swing and initial contact, which was significantly greater than in the toe-walkers.