The purpose of this thesis was to examine social workers perceptions of foster care placements in general and network placements in particular in order to understand how their perceptions affect the child's legal security. Based on the purpose, two research questions were formulated: What influences social workers' assessments of placing children within the network versus in unfamiliar foster homes? How do social workers describe their discretion in decisions regarding the placement of children, and in what way can this discretion be understood from a perspective of legal certainty?

In order to achieve understanding in the subject, we used a hermeneutic scientific approach. A qualitative study was conducted in the form of semi-structured interviews with eight social workers. The interview results were analyzed through a thematic analysis using previous research and theories on discretion and legal security.

The result of the thesis showed that there are many aspects that affect social workers in their assessments of placing a child within or outside the network. Among other things, attachment and a sense of belonging were highlighted as important aspects for a foster care placement. However, social workers were critical of these aspects being sufficient for a foster home to be considered suitable and in the child's best interest. The results also showed that social workers largely highlight limitations rather than opportunities in relation to their discretion. From our interpretation, discretion may mean that each social worker needs to provide the child with a legally secure assessment, as foster care placements require an interpretable law due to their complexity.