CWI has been investigating the placement and use of high-speed networks for use in international, national and local communication. As part of a multi-year grant from the Dutch Government, we are currently upgrading our local network infrastructure to make use of ATM technology, providing an environment to support research in areas such as multimedia and scientific visualization, and to improve general network service to our users. We have conducted several performance tests during the past year to familiarize ourselves with the technology and its potential in servicing user needs. Our initial results indicate that while installation of network interfaces is relatively trivial, much work remains to be done before the full potential of high-speed communication can be enjoyed by general applications.