The FLARE Index to Treaties Extended – The FLARE Index to Treaties (FIT), launched in March 2009 on the Institute of Advanced Legal Studies web server has been extended to cover about a third more treaties and conventions. In the past two years the Index has established itself as a valuable finding tool for the international lawyer. It is a fully searchable database now indexing and listing over 2,000 of the most significant multilateral treaties concluded from 1353 onwards and a number of significant bilateral treaties signed between 1353 and 1815. This article, by Steven Whittle and Peter Clinch describes the background to the extension and technical aspects of the updated implementation employed to deliver new content and finding features.