A series of Specifications (all parts of S-631) was prepared under a Joint Industry Project 35 (JIP35) by the ‘Offshore Structures Specifications Task Force’ organized by the International Association of Oil & Gas Producers (IOGP) with support from the World Economic Forum (WEF). The work has developed a minimized set of supplementary requirements for the design and operation of offshore structures based on a critical review of the ten participating members’ company specifications, building on recognized industry and/or international standards.