A conference on mammalian cell mutagenesis was held at the Banbury Center, Cold Spring Harbor, NY, USA, March 22-25, 1987. The objective of the conference was to provide a forum for discussions concerning the genetic, biochemical, and molecular basis of induced mutations in standard, and in newly developed, mammalian mutagenesis assays. The meeting was intended to extend the focus of the Banbury 2 Conference on Mammalian Cell Mutagenesis to include recent developments in commonly used mammalian cell mutagenesis systems, as well as to provide available molecular data evaluating the mechanistic pathways involved in mutational processes in mammalian cells. Of particular significance was the presentation of data that analyzes quantitative differences in observed radiation and chemical-induced mutant frequencies at different selectable loci. Such differences have important implications in the interpretation and analysis of data derived from defined mammalian cell specific-locus assays. (Copyright (c) 1988 Elsevier Science Publishers B. V.)