This paper reports on our experiences with using the emerging Web service technologies and tools to create a demonstration information broker system as part of our research into information management in a distributed environment. To provide a realistic context, we chose to study the use of information in the healthcare domain, and this context sets some challenging parameters and constraints for our research and for the demonstration system. In this paper, we both report on the extent to which existing Web service technologies have proved to be mature enough to meet these requirements, and also assess their current limitations.

We address the problem of large-scale data integration, where the data sources are unknown at design time, are from autonomous organisations, and may evolve. Experiments are described involving a demonstrator system in the field of health services data integration within the UK. Current Web services technology has been used extensively and largely successfully in these distributed prototype systems. The work shows that Web services provide a good infrastructure layer, but integration demands a higher level "broker" architectural layer; the paper identifies eight specific requirements for such an architecture that have emerged from the experiments, derived from an analysis of shortcomings which are collectively due to the static nature of the initial prototype. The way in which these are being met in the current version in order to achieve a more dynamic integration is described.