Families with multiple and complex problems have become the primary client group of modern child protection services. The challenge for child protection services is to respond holistically to address inter-related problems, in order to better support families to make and sustain changes to better meet the needs of children. This paper investigates the separate impacts of parental substance misuse, domestic violence and parental mental health problems. It presents evidence regarding the extent to which these problems co-occur and a discussion of the wider context of exclusion and disadvantage, its causes and its consequences. Finally, it provides an overview of research and theory for working with families with multiple and complex problems.