This paper describes the testing strategy, methods and tools used for testing a distributed financial services system on the Internet with CORBA interfaces for handling a high volume of queries to a relational database. The new system architecture was derived by reengineering a previous more limited application. The paper starts with an outline of the software architecture, the testing requirements and the testing strategy. It then goes on to describe the tools used in the project and the results achieved. For the project a generic C++ integration test framework was developed especially for testing distributed components. This tool is described in detail. The paper ends with a discussion of the discovered defects and their distribution. Copyright © 2002 John Wiley & Sons, Ltd.