Fontes Anglo-Saxonici: A Register of Written Sources Used by Authors in Anglo-Saxon England is intended to identify all written sources which were incorporated, quoted, translated or adapted anywhere in English or Latin texts which were written in Anglo-Saxon England (i.e. England to 1066), or by Anglo-Saxons in other countries. The material is compiled in the form of a database which analyses each Anglo-Saxon text passage by passage, sentence by sentence or, if necessary, phrase by phrase, identifying the probable source-passages used for each particular segment. The database now contains over 28,000 records analysing in detail the source-relationships of around 1143 Anglo-Saxon texts (over 500 Old English and over 600 Latin) and identifying the use of over 1000 sources and analogues. These numbers continue to grow rapidly as we add records to the database. The database shows which texts were known in Anglo-Saxon England, how well specific texts and authors were known, and in what different ways they were used. It also provides the basis for studies on the intellectual interests of Anglo-Saxon authors, and what contributions the Anglo-Saxons made to the history of ideas.