Streams of data often originate from many distributed sources. A user wanting to query the streams should not need to know from where each stream orginates but should be provided with a global view of the streams. R-GMA is a system that integrates data streams to provide a global view of all the streams for users to query. R-GMA has been developed as a grid information and monitoring ayatem although the techniques developed can be applied wherever there is a need to publish and query distributed streams.