Child protection proceedings often concern children with international connections. In recent years, the courts of England and Wales have handed down a number of significant judgments examining the application of international legal instruments (in particular Brussels IIa) to care proceedings. This article considers the impact of court judgments on practical 'working' by Local Authorities in international child protection cases. A case study was conducted, oriented by socio-legal theory, consisting of a small number of qualitative interviews with Local Authority lawyers and social workers. The article concludes that some judgments have acted as a catalyst to change working practices for Local Authorities. However, international child protection cases present a variety of challenges for Local Authorities, and judgments provide an imperfect site for the provision of procedural and substantive guidance in this complex area. Further, there is often a tension between the need to conscientiously adhere to such guidance, and the welfare needs of the children with whom the Local Authority was concerned.