Firms face the challenge of working with other firms in their business network so as to increase the value of products and services offered to end customers and consumers. This often requires managers to invest in developing strong and effective business-to-business relationships. This paper explores how a buyer and supplier draw on their own identities and the identities of each other in ways that enable them to develop a basis on which to conceptualise and operationalise a strategic sourcing relationship. We conducted an in-depth, longitudinal case study of a buyer-supplier relationship which involves a manufacturer buying and complex design services. The study suggests that the corporate identity of companies involved in a relationship has a prominent role in informing development of the relationship.