Emeritus Professor of Medieval History, University of Reading, UK. Senior Fellow at the National Humanities Center, 1998-9. Fellow of the Royal Historical Society. Corresponding Fellow of the Medieval Academy. Retired 2005. Main books: The Trial of the Templars (CUP, 1978, 2006); The Two Cities: Medieval Europe, 1050-1320 (Routledge, 1992, 2004); The New Knighthood. A History of the Order of the Temple (CUP, 1994); The Cathars (Longman, 2000, 2013); The Crusader States (YUP, 2012).