TACWeb (TAC images on the Web), is a web-based Grid Portal, developed at the CACT/ISUFI laboratory of the University of Lecce for the management of biomedical images in a distributed environment. TACWeb, building on top of the Globus Toolkit, is an interactive environment that deal with complex user?s requests, regarding the acquisition of biomedical data, the "processing" and "delivering" of biomedical image, using the power and security of computational grids. Recently, Grid technologie are being integrated with Web Service technologies to provide a framework for interoperable application-to- application interaction. In this paper we present an evolution of the TACWeb architecture that is compliant with the Web Service approach and it main functionalitie. In such a system, the basic capabilities are encapsulated and exposed as Web Services allowing the development of new health applications as a composition of such services.