GenerationPMTO (Parenting Through Change) is a parenting programme. It is a targeted-selected and targeted-indicated programme delivered to groups of families of children and young people between the ages of 3 and 18, where there is a risk of developing externalising or internalising behaviour problems. The programme can also be delivered to families where these problems have begun to emerge, and to birth parents of children/youth who are in foster care. It aims to reduce children and young people's behaviour problems, improve their school functioning and social relationships, and prevent involvement in the criminal justice system and substance use. A version of the programme delivered to individual families (rather than to groups of families) is available.