Foster children experience a lot of stress because of their life histories and changes in their family circumstances, such as foster care placement. It is important that foster parents recognize the early signs of stress in foster children and learn how to act in a non‐threatening and understanding manner. Family‐based interventions may help in this. In this paper, we report on a meta‐analysis of studies (n= 19) of the effectiveness of such interventions. All studies used a pre‐test/post‐test design. Both problem behaviour in foster children and the parenting skills of foster parents improved by 30%; however, none of the interventions were specifically intended to help young children (<4 years) to cope with stress. The importance of interventions for young foster children is discussed, as well as the necessary elements these interventions should include.