Behavioral changes for 76 adults and 115 children from 62 families participating in a Family Treatment Drug Court (FTDC), in either residential or outpatient settings, were studied. Improvements in psychosocial functioning were calculated using a reliable change index (RCI) for family, adult, and child measures. Among outcomes, significant improvements in family functioning were noted and associated with improvements in child development and the likelihood of reunification. Support for FTDCs and implications for future practice and research are discussed.