The evaluation of the Manchester Motor Skills (MMSP) project uses a programme theory driven evaluation approach. The research literature proposes the consideration of implementation and impact models. The implementation model is developed in order to establish the full range of implementation factors that need to be attended to for successful initial and long term implementation of the MMSP in schools. An impact model is proposed, based upon key elements from the implementation model and is to evaluate the success of the MMSP in 10 schools at the levels of; groups of children receiving the programme, teaching of the programme and improving school systems for meeting the needs of children with motor difficulties.