Xaira is the current name for a new version of SARA, the text searching software originally developed at OUCS for use with the British National Corpus. This new version has been entirely re-written as a general purpose XML search engine, which will operate on any corpus of well-formed XML documents. It is however best used with TEI-conformant documents. Xaira has full Unicode support. This means you can use it to search and display text in any language, provided you have a suitable Unicode font installed on your system. At the heart of Xaira is the Xaira Object Model. This defines a range of objects and methods for representing and searching large amounts of linguistic data. The Xaira Server program implements this model. The Xaira Indexer program creates platform-independent indexes from collections of XML documents for use by the Server. Both these Xaira components can be deployed on any platform. Client programs can access a Xaira server using a close-coupled API such as that used by the Windows client (which is written in C++), or via XMLRPC or SOAP. We provide a fully-featured client for Windows, and simpler demonstration clients written in Java and in PHP. All versions of Xaira are now distributed free of charge under the GNU General Public Licence.