One of the goals of procurement is to establish a competitive price, while e-procurement utilises electronic commerce to identify potential sources of supply, to purchase goods and services, to exchange contractual information and to interact with suppliers. Extensive academic work has been extensively devoted to e-procurement in diverse industries. However, applying e-procurement in the healthcare sector remains unexplored. It lacks an efficient e-procurement mechanism that will enable hospitals and healthcare suppliers to electronically exchange contractual information, aided by the technologies of optimisation and business rules. The development and deployment of e-procurement requires a major effort in the coordination of complex interorganisational business process. This article presents an e-procurement optimised system (EPOS) for the healthcare marketplace, a complete methodological approach for deploying and operating such system, as piloted in public and private hospitals in three European countries (Greece, Spain and Belgium) and suppliers of healthcare items in the fourth country (Italy). The efficient e-procurement mechanism that EPOS suggests enables hospitals and pharmaceutical and medical equipment suppliers to electronically exchange contractual information.