In this paper we propose a conceptual model for e-procurement solutions for industrial services. Product-related services are of particular interest of companies and should be supported through an appropriate network strategy. However, in the service field, e-business solutions and current standards are still not or only partially considering specifications and related variables of services. We make an approach to develop a conceptual model which allows analyzing existing systems and to specify requirements by distinguishing four system levels. Services can be classified using criteria such as degree of tradeability, intangibility, degree of labor intensity or interaction, etc. In the context of collaborative networks and professional services another common variable is the level of customer contacts or interactions. Services looked at in this paper require close buyer-supplier relationships in nature, and motivate to apply collaborative networks as a strategy, as trust between buyer and seller can be seen as a central focus.