Parents who use opioids and are involved in the child welfare system are less likely to retain custody of their children than parents who use other drugs. No previous studies have described medication-assisted treatment (MAT) utilization and child permanency outcomes for this population. The Sobriety Treatment and Recovery Team (START) model is a child welfare-based intervention focused on families with co-occurring substance use and child abuse / neglect issues. This study examined the prevalence and correlates of MAT utilization among parents in the START program with a history of opioid use, and compared child outcomes for families who received MAT services to those who did not. Of the 596 individuals with a history of opioid use in the START program, 55 (9.2%) received MAT. Receipt of MAT services did not differ by gender, age, county of residence, or drug use, though individuals who identified as White were more likely to participate in MAT. In a multiple logistic regression model, additional months of MAT increased the odds of parents retaining custody of their children. To address barriers to MAT, results-focused educational interventions may be needed for the child welfare workforce, as well as programs to improve collaboration and decision-making between the child welfare workforce, court personnel, and drug addiction treatment providers. (C) 2016 Elsevier Inc. All rights reserved.