The American Peptide Society (APS) provides a forum for advancing and promoting knowledge of the chemistry and biology of peptides. The approximately one thousand members of the Society come from North America and from more than thirty other countries throughout the world. Establishment of the APS was a result of the rapid worldwide growth that has occurred in peptide-related research, and of the increasing interaction of peptide scientists with virtually all fields of science. Peptides for Youth: The Proceedings of the the 20th American Peptide Symposium will highlight many of the recent developments in peptide science, with a particular emphasis on how these advances are being applied to basic problems in biology and medicine. The 20th American Peptide Symposium will take place June 26 - 30, 2007 in Montreal, Canada.