Triazenes: Synthesis and Chemical Properties.- Mechanisms of the Biological Actions of Triazenes.- Triazenes and Triazene N-Oxides: Antitumour Action in Animal Tumour Systems.- Antimestastatic Action of Triazene Derivatives.- Effects of Triazenes on Immune Responses.- Xenogenization of Experimental Tumors by Triazene Derivatives.- The Metabolism of Antineoplastic Triazenes.- Notes on the Metabolism, Pharmacokinetics and Mode of Action of N-Methyl and N-Ethyl-Triazenes in Relation to Their Pharmacological Activity.- Clinical Use of Triazenes.- Clinical Studies with the p-Carboxyl-Dimethyl-Phenyl-Triazene CB10-277.- Triazenes: Therapeutic Considerations and Perspectives.- Antitumor Imidazotetrazines: Prodrugs Targeted to the Major Groove of DNA.- O6-Alkylguanine-DNA-Alkyltransferase Gene Expression and the Cytotoxicity of Triazenes.- N-Methylmelamines, a Unique Class of Anti-Tumour Agents?.- Experimental Background and Early Clinical Studies with Imidazotetrazine Derivatives.- 'O6-Alkylguanine-DNA-Alkyltransferase: Significance, Methods of Measurement and Some Human Tumor and Normal Tissue Levels' (Contributions of the Workshop).- Summary of Poster-Sessions.- Contributors.