This chapter examines some of the factors affecting interagency support for families with a mentally ill parent across Europe. One of the most important factors is the key part played by resources in the provision of early, expert interventions. Recent research from Sweden reinforces the notion that proper resourcing has the potential to make a significant difference to the lives of the children concerned. In spite of the difficulties that children with a mentally ill parent face, this research suggests that extensive supportive services in health, welfare and education can help them to overcome their disadvantages. It is learned from the comparative research that there is an interaction of factors to facilitate or hinder interagency cooperation. From European practitioners working under different conditions and systems, from Scandinavia to the Mediterranean, it is found out that a shared sense of responsibility enables professionals to work flexibly to circumvent potential obstacles.