Abstract: The consensus that XML has become the de facto standard for data interchange will spur demand for technology that allows users to integrate data from a variety of applications, repositories, and legacy systems which are located across the corporate intranet or at partner companies on the Internet. In the past two years, Nimble Technology has developed a product for this market. Spawned from over a person-decade of data integration research, the product has been deployed at several Fortune-500 beta-customer sites. This abstract reports on the key challenges we faced in the design of our product and highlights some issues we think require more attention from the research community.