Bachelor's thesis deals with the cooperation of the social worker with the birth family and with the types of assistance offered to the birth family during foster care so that the child can return to his family. It also discusses the cooperation and assistance of the center for social work to the foster family and the mutual cooperation between the birth and the foster family. The theoretical part of the thesis discusses various topics, namely the definition of foster care and other terms related to foster care, foster care legislation and the cooperation and support of the center for social work, which also includes other sub-themes. A qualitative study was carried out in the empirical part. It was conducted by interviewing social workers using pre-established guidelines. The survey sample includes six social workers from different centers for social work employed in foster care. In the empirical part are also presented the results that answer the following research questions: how does the social worker interact with the mother during a foster care, what kind of help does the social worker provide to the birth family so that the child can return to it, in what way does the social worker interacts with the foster family when the child is in foster care and in how does the social worker encourages the interaction between birth and foster family.