Isdat is a client-server system that provides access to scientific data, primarily developed for and by the Wave Experiment Consortium on the Cluster satellites. The server part of Isdat has modules to read various types of data and present them in a unified format for the clients. On the client side, there is a high-level generic browser client (igr), as well as specialized clients and APIs for C, Matlab, IDL and Java. This allows users to access data from different sources (ISDAT servers) in a unified way.