The alternating copolymerization of carbon dioxide and epoxide to produce polycarbonate has attracted the attention of many chemists because it is one of the most promising methodologies for the utilization of carbon dioxide as a safe, clean, and abundant raw material in synthetic chemistry. Recent development of catalysts for alternating copolymerization is based on the rational design of metal complexes, particularly complexes of transition metals with well-defined structures. In this article, the history and recent successful examples of the alternating copolymerization of carbon dioxide and epoxide are described. (C) 2004 Wiley Periodicals, Inc.