A sample of the most exciting developments in the cloning, manipulation, expression and application of genetically-engineered monoclonal antibodies. This rapidly-evolving field has witnessed the PCR combinatorial cloning of vast immunological diversity, in vitro mutagenesis of MAbs, MAbs created by transgenic animals, novel expression systems in plants, animals and lower systems, as well as a rich variety of genetically modified MAbs as potential therapeutic agents. Leading scientists from academia and industry present their own findings as well as short reviews of these research areas.