The purpose of the study was to investigate children's participation in child welfare investigations. Six interviews were conducted with social workers who are active in child welfare investigations, to understand social workers experiences of children's involvement in investigations. The results show that children are not always involved or as involved as they should, for different reasons. The child's age, the child's ability to communicate, the child's attitude to cooperation, the guardian's attitude to cooperation, social workers prerequisites in terms of skills, tools and workload. Furthermore, the results show that children's best and social issues need to weigh heavier in child welfare investigations, as today there is a lot of focus on parents and guardians. This study aims to contribute knowledge of children's participation in child welfare research.