The Ship's Machinery Committee, at the direction of the Steering Committee of the Society of Naval Architects and Marine Engineers' Technical and Research Program, on 11 March 1964 formed Panel M-21 (Automation of Ship's Propulsion Plant). The task of the panel was to examine the design and operational practices and from these considerations develop criteria for technical guidance in establishing the desired degree and methods for employing centralized control and automating a ship's propulsion plant. In December 1970, the work of Panel M-21 was published in SNAME Technical and Research Bulletin No. 3-23, "Guide for Centralized Control and Automation of Ship's Steam Propulsion Plant". A new guide on gas turbine automation was begun in June 1972 with the same objectives as the earlier guide on steam automation. This guide prepared by a consensus of the M-21 panel represents the diverse expertise of the panel members. However, the philosophy and implementation concepts of centralized control and automation presented here are not the only approaches in this rapidly developing field. Valuable additional information is available from classification societies, professional organizations, industry, and government agencies.