A reassertion of the value of relationships in UK practice with children in care is underway after a period when outcome focused work obscured their importance. But little is specified in the training requirements for foster carers or residential care workers about how to construct and maintain high quality relationships. This paper presents evidence from a study of understandings of professional-child relationships in three continental European countries that are informed by social pedagogy and from social pedagogues working in England. Four purposes of relationships are identified that hinge on questions of whether the relationship is about facilitating another objective such as building children’s skills, participation in society, taking action on their behalf, or about being together in an ethical encounter. The paper then discusses the role of trust in relationships and the deployment of the self. It concludes by identifying four practical indicators for social pedagogic professional-child relationships. They should be: present and future orientated; founded on practical actions; they require awareness of how the worker uses their ‘self’; and a supportive organisational environment.