The relationship between family functioning, social support, and medication compliance in 32 renal transplant children and their parents was examined. Results indicated that children whose fathers gave more emotional support or were more informative were less compliant with azathioprine and cyclosporine (P < 0.05 for both). Children from families experiencing numerous stresses were also found to be less compliant with azathioprine (P < 0.05). Finally, compared with older children, younger children were found to be less compliant with cyclosporine (P < 0.005). Implications for predicting child adherence and for future research relating to compliance with multidrug regimens are discussed.