The focus of this thesis was to understand the influence of a conceptual model of practice upon occupational therapists in a British health and social care setting. Case study methodology was used to explore the clinical practice of Occupational Therapists (OTs) in one county in England who implemented the Canadian Model of Occupational Performance (CMOP) (CAOT 1997a, 2002). The research focused upon a deeper understanding of the complex interactions between individual factors and the case being examined. This required examination of three sources of data, namely meeting minutes, artefacts and participant interviews. Each was examined separately and then themes from all three units were examined to identify themes from across the dataset to understand inter-relationships to support the development of theoretical propositions and contribute to theory building. This study identified that use of a single model, the CMOP actively encouraged practice development in this county and was a dynamic and multifaceted social process.