XQuery is the soon to be standard for querying XML data sources. It provides a host of features that allow precise and expressive definition of queries over XML documents and over data sources that can be viewed through equivalent XML models. Apart from being an effective query language, it can also be used gainfully for XML transformations. It would be particularly useful in cases where the transformations are not just for presentation but have other prerogatives such as a strong requirement for preservation of types (such as transformations of business documents between systems that use incompatible formats). Given these applications, XQuery is likely to become an important technology for data and application integration. This session will introduce the audience to the XQuery language and discuss some real world applications of XQuery in data and appplication integration with some demonstrations of such applications.