Collaborative relationship in social work is a relationship in which the process of helping is established and is based on the realization of the process of change, dialogue and involvement of the user in the creation of solutions together with the expert. The focus of this paper is the relationship between experts and users in social work with families. The goal of the work was to gain insight into the application of elements of cooperative relations in social work with families from the perspective of social workers in two regional offices of the HZSR. In view of this, the research questions included the contribution of the current reform of the social welfare system in the work of social workers with families in HZSR; what elements of cooperative relationship social workers use in their work with families and what professional needs do social workers have in the professional unit for children, youth and families within the HZSR regional offices. The results of the research showed that there were no changes in the Professional Unit for Children, Youth and Family, and the participants mentioned several aggravating factors resulting from the reform. Of the professional competencies, the most present are process competencies and the need for support, improvement of working conditions and employment of various experts in the Regional Offices. The results also show how and which elements of a collaborative relationship social workers apply in their work with families. Although the results of this research cannot be generalized to all HZSR regional offices, this research can be extended to other offices, which would enable further knowledge and comparison of results. The results of such research could contribute to the understanding of the reasons for the application of elements of a cooperative relationship in work with families and the changes that were potentiated by the reform of the social welfare system from the perspective of social workers.