Two studies were conducted to examine the effects of motivational climate on motor-skill development and perceived physical competence in kindergarten children with developmental delays. In Experiment 1, two intervention groups were exposed to environments with either high (mastery climate) or low autonomy for 12 weeks. Results showed that the mastery-climate group demonstrated significantly better locomotor performance and higher perceived physical competence postintervention than did the low-autonomy group, although both groups improved in locomotor and object-control skill performance. The second investigation extended the findings of the first by determining that the intervention effects were present 6 months later. In summary, the mastery-climate group showed positive changes in skill development and perceived physical competence, and this positive pattern of change was maintained over time.