For the purpose of this paper, supply chain management is the process of planning, implementing, and controlling the operations as efficiently as possible within the sales and marketing environment. The supply chain spans the tracking of all transactions from the identification of prospective customers; through quote to order conversion; fulfilment; and on to post sales support. As an intense human activity customer supply chains are wholly dependent on knowledge and require social network activity to transfer that knowledge to the point of need in order to reduce process variation. This paper builds upon work undertaken previously by the author, which developed an organisational model of the social interactions affecting knowledge transfer within organisations (Smith et al 2003). This paper also discusses the problems of knowledge location, the ability to share (as well as willingness); the prevention of knowledge attrition through a programme of knowledge definition (codification); knowledge retention; and knowledge transfer across the customer interface. The argument is made that whilst much information is being shared, the knowledge that makes such information useful must also be transferred or new desired outcomes will not emerge. In order to share such knowledge, lessons were learned from three major studies that were carried out in 2004, 2006 and 2007; to determine the extent of failure to transfer knowledge within the sales and marketing supply chain at Ordnance Survey. As a result of these studies, a programme of work was put in place to identify knowledge silos, acting as centres of excellence in the supply chain putting in place a project to preserve and transfer knowledge from these silos, to facilitate learning and reduce knowledge attrition. This paper focuses on empirical evidence from these studies and the impact that this knowledge management project has had on the efficacy of the supply chain to deliver the desired outcomes.