The goal of this paper is to expound upon the lessons learned from past efforts to integrate child welfare services and drug treatment services. It is hoped that by reviewing best practices in this field, more agencies will learn from past efforts and forge their own collaboration of these services. The paper explains that millions of children have been abused or neglected by parents who have substance abuse problems. However, child welfare agencies and drug treatment programs often do not collaborate or offer a continuum of care for those seeking their services. Additionally, while drug abuse problems are often thought of as the cause of child abuse or neglect, the opposite may also be the case. Incidents of child abuse may lead the child to a life of drug and alcohol abuse. As such, it is imperative that linkages be made between these two service agencies in order to better address the needs of this population. After outlining the problem in chapter 1, the paper goes on to explain policies relevant to service agencies dealing with child welfare or substance abuse problems. Chapter 3outlines various recent innovations in the child welfare system, including different models of treatment and concrete suggestions for child welfare workers. Chapters 4 through 10 offer specific case studies of successful collaborations between child welfare and drug treatment services from around the country. The last two chapters discuss the findings from the case study sites and the lessons learned in forging the collaborations among agencies. Specific recommendations are made concerning client intake, joint accountability, and staff training and development. Appendices offer various tools to serve as guidance for future collaboration projects.