The purpose of this paper is to investigate how information systems are used by knowledge-intensive service firms and identify their effects on client-provider interactions. The paper uses data from case studies of service-related departments of three multinational firms. We identified several broad trends present in all three case companies. The required degree of knowledge specialisation, coupled with the ability to leverage knowledge created during service interactions resulted in high degrees of knowledge asymmetries between service provider and clients, which led to clients becoming the recipients of knowledge rather than co-creators. Differences between the cases related to the varying degrees to which information systems had been used to support service interactions. We therefore provide a model that outlines three key phases of activity. Individualisation involves the categorisation and location of tacit knowledge. This was followed by the codification and leveraging of service interactions through standardisation. Finally, the ability to provide alternative, more customised services, was achieved through modularisation. Increasing levels of specialisation of labour resulted in increasing knowledge asymmetries between service provider and client, reducing the need for client participation and co-production. Firms progress through three stages of development using information systems to support leveraging knowledge required for service delivery. The findings are based on case studies of departments within three multinational firms and would benefit from further empirical testing. The paper contributes to the existing literature in several ways. It focusses specifically on knowledge-intensive service firms, where labour is highly specialised. It gives information systems an explicit and significant role in examining how service elements may be leveraged. Finally, it outlines an exploratory model for managing this process.