The process of mutagenesis provides the raw material for evolution, and is causative in a number of human diseases. This conference will focus on the mechanisms that generate mutational intermediates as well as the diverse processes that remove or influence the fixation of these intermediates. Relevant topics include DNA replication fidelity, hypermutable and at-risk sequences, cell cycle checkpoints, excision repair mechanisms, mechanisms of lesion tolerance, directed mutations and genome rearrangements, genotype-phenotype relationships, and human disease and cancer. Presentation of unpublished results will be emphasized, and active discussion by all participants will be encouraged.