To examine the hypothesis that the degree of maternal compliance with physical therapy regimens for cystic fibrosis (CF) is correlated with the child's psychological adjustment, compliance was classified by independent raters as “moderated‘’ (intermediate) or “unmoderated‘’ (rigid adherenceorclear noncompliance). Compliance data were obtained in a structured self-report interview. The Piers-Harris Children's Self-Concept Scale was administered to the children (23 boys, aged 7–15 years) to measure this dimension of psychological adjustment. Children of mothers with unmoderated compliance scored significantly lower on total self-concept scores and on subtests measuring popularity and physical appearance and attributes than those with mothers whose compliance was rated as moderated. These findings, if confirmed in studies with larger samples that include girls with CF, have implications for practitioners who treat children with this disorder.