Introduction -- DNA synthesis errors, mutators and cancer -- DNA polymerase and the control of DNA damage induced mutagenesis in eukaryotes -- Patterns of mutation in cancer cells -- Mismatch repair and cancer -- Genomic instability and tolerance to alkylating agents -- The relationship of DNA methylation to cancer -- Neoplastic transformation: the contrasting stability of human and mouse cells -- Damage inducible mutagenesis: recent insights into the activities of the Umu family of mutagenesis proteins -- The relevance of bacterial mutators to understanding human cancer -- Mutation in resting cells: the role of endogenous DNA damage -- TP53 tumour suppressor gene: clues to molecular carcinogenesi and cancer therapy -- Telomere maintenance in tumour cells -- Regulation of genomic instability in preneoplastic cells -- Chromosome abnormalities in leukaemia: the 11q23 paradigm -- Clonal chromosome abnormalities in neoplastic cells: evidence of genetic instability? -- DNA damage detection by DNA dependent protein kinase and related enzymes -- Mammalian X ray sensitive mutants: a tool for the elucidation of the cellular response to ionizing radiation -- Mechanism of V(D)J recombination -- Transrearrangements as biomarkers for risk of lymphoid malignancy -- Many mutations in cancers.