The purpose of this study is to investigate how children who have been exposed to violence between their parents are involved in the social workers investigation process. For this study the empirical material has been collected through six qualitative and semi-structured interviews with social workers who are working with child protection cases. Through the study we explore social workers' descriptions of the children's involvement, and what factors they emphasize as limiting and enabling for the children's participation in the investigation process. By an analysis with the help of The Lundy model and Shier’s model of participation, we found out that children's age and maturity are a recurring pattern in terms of the extent to which children become involved and how their opinions are taken into account in the investigation process. The interviewees emphasize that there are different ways to involve the children based on children's different conditions, for example through observations and conversation methods. There are no one-sided explanations of how children exposed to violence were involved in social workers' investigation processes, but participation was influenced by a number of factors. The factors that the interviewees describe as limiting and enabling are structures in the organization, laws and methods, and parents.