Parental cooperation with social services in child maltreatment cases is fundamental to all forms of family intervention. If rehabilitation efforts fail and the child cannot be safely reunified with his parents, the state is authorized to initiate termination of parental rights (TPR) proceedings. Given the scant literature on parental cooperation and TPR, the present study examined associations between parental cooperation and TPR in Israeli court cases of child maltreatment. Comparisons between uncooperative (n = 106) and cooperative parents (n = 155) revealed that uncooperative parents were more than three times more likely to have their parental rights terminated than cooperative parents, controlling for child and parent characteristics. Parents who did not cooperate with social services had high levels of mental health problems, substance abuse, criminal records, and poverty and their children had more mental health concerns and suffered more from neglect. We discuss the important implications resulting from these findings, which include: the need to view the engagement of parents in the child welfare process as a specific goal in itself and develop research-based models specifically targeting multiple-problem families at high risk of TPR; the need for professionals to build a good working alliance with parents in order to strengthen their participation; the need to take into account different background conditions and stressors related to the parents in order to facilitate greater cooperation; and the need to assess the potential mental health needs of children involved in cases of maltreatment with low parental cooperation.