Abbot is a free tool for converting multiple XML texts with multiple markup schema into a common interoperable file, offered by the MONK (Metadata Offer New Knowledge) Project. It can also read an XML schema file and output procedures, and use them to convert other files into valid XML in alignment with the target schema. While Abbot focusses on TEI, it has been designed to flexibly accomodate other standards and can transform texts into any XML schema required.