Effective customer-related knowledge transfer can be seen as the cornerstone of customer value creation in collaborative relationships between professional service organisations and their customers. Our intention in this paper is to describe how different work groups within organisations (communities of practice) influence the perceived customer value. We approach this phenomenon from a relationship management perspective and use literature from relationship marketing, organisation research and knowledge management as a theoretical basis. Empirically the paper is based on an information-rich explorative case study of a professional service organisation, operating in the consultancy and training business, and its relationship with one of its customers.