This volume contains edited contributions from the speakers at the NATO Advanced Research Workshop on "DNA Repair Mechanisms and Their Biological Implications in Mammalian Cells" held October 1-6, 1988, at the Abbaye Royale de Fontevraud, Fontevraud France. The meeting was dedicated to Paul Howard- Flanders (Yale University, New Haven, CT. , 1919-1988), whose seminal con­ tributions to the DNA repair field include the cO-discovery of the excision repair pathway, the elucidation of post-repli­ cation repair in E. coli, the isolation of the lexA and recC mutants, and his extensive work on the enzymology of RecA. A plethora of recent developments in DNA repair mechan­ isms and related processes in mammalian cells have advanced our understanding