The Systemic Practice Model (SPM) is a Finnish adaptation of the Reclaiming Social Work (RSW) model, which incorporates systemic ideas and practice into children’s social care. This study is the first attempt to evaluate the effectiveness of the RSW model outside England. The study employed a quasi-experimental repeated measures design. Questionnaires assessing child- and family-level outcomes and the quantity (i.e., number of meetings) and quality (i.e., service user feedback) of the practice were administered to social workers, children and parents twice over a six-month follow-up period. Outcome data comprise 112 cases (SPM cases n = 56, service-as-usual cases n = 56) from 18 child protection teams (SPM teams n = 9, service-as-usual teams n = 9) at three sites. The overall need for child protection decreased across the sample during the follow-up period. While the intensiveness of practice was higher in the SPM group, no significant differences were found between the study groups in practice outcomes or service user satisfaction with child protection. The limitations and implications of the study for future research are discussed.