The Common Assessment Framework (CAF) and lead professional (LP) working are part of a government strategy in England and Wales for earlier intervention and more integrated services for children and families. A national government evaluation studied the early piloting stage of implementation of CAF and LP working in 12 English trialling group areas. Initial findings suggest a number of interlocking factors, which seem to either help or hinder the process of implementation. Where there is enthusiasm for the work and a clear structure, which is understood and internalized by practitioners, CAF and LP are promoting better multi-agency working, helping agencies to come together much faster and enabling more rigorous follow-through of services. Hindrances include the lack of a local history of successful multi-agency working, which seemed in turn to breed professional mistrust and fuel anxiety. Anxiety is also generated by fears about change and lack of confidence in new skills. For many practitioners aspects of this work are new and the emotional impact of the work needs to be acknowledged in support and training. The task of local implementation would be easier if there were firmer national guidance about CAF and LP roles and processes, for example a single nationally approved CAF form.