The Troubled Families programme is about change – for families and for services, and this report is an aid for that change. It is a tool to help local authorities and their partners, who have asked for guidance on how best to work with troubled families, and for the evidence about family intervention to be brought together in one place. The report looks at academic evidence, local evaluations of practice, what practitioners have told us works in their services and what families tell us makes this work different and successful for them.