A Biographical Dictionary of Dark Age Britain : England, Scotland, and Wales, c.500–c.1050 (avec Alfred P. Smyth et David Kirby), B. A. Seaby, Londres, 1991.
The English and the Norman Conquest, Boydell & Brewer, Woodbridge, 1995.
Kingship and Government in Pre-Conquest England, c. 500–1066, Macmillan, Londres, 1999.
Æthelred the Unready : the ill-counselled king, Hambledon and London, Londres, 2003.
A Dictionary of Medieval Terms and Phrases (avec Christopher Coredon-Stoute), Boydell & Brewer, Woodbridge, 2004.
The World Before Domesday : the English aristocracy, 900–1066, Continuum, Londres, 2008.