The ten volumes of A COMPLETE CONCORDANCE TO THE WORKS OF GEOFFREY CHAUCER make possible systematic studies of Chaucers language and text for the first time. They have a great potential as a standard research tool for English medievalists, historians of the language and historians of ideas. They allow students of Chaucer's syntax to analyse common and high-frequency words in their contexts. The Concordance is based on the Riverside Chaucer published under the general editorship of Larry d. Benson (Boston 1987, and Oxford 1988). The two volumes of A RHYME CONCORDANCE TO THE POETICAL WORKS OF GEOFFREY CHAUCER are a sequel to the Concordance. The Rhyme Concordance is the first of its kind. The five volumes of A LEXICAL CON¬CORDANCE TO THE WORKS OF GEOFFREY CHAUCER are a sequel to the Concordance as well. A Lexical Concordance To The Works Of Geoffrey Chaucer is lemmatized and largely based on the Middle English Dictionary, all morphologically variant forms of a word are gathered under a convenient heading, as in most dictionaries.