The Fourth Greater Mekong Subregion (GMS) Summit opened at the Myanmar International Convention Center here Tuesday under the theme \"Beyond 2012: Towards a New Decade of GMS Strategic Development Partnership\". Chairman of the summit Myanmar President U Thein Sein made a statement at the opening ceremony. Leaders of the six GMS countries -- Chinese State Councilor Dai Bingguo, Cambodian Prime Minister Hun Sen, Lao Prime Minister Thongsing Thammavong, Myanmar\'s President U Thein Sein, Thai Prime Minister Yingluck Shinawatra and Vietnamese Prime Minister Nguyen Tan Dung attended the opening ceremony. The meeting also gathered together GMS ministers, GMS delegations, ADB staff and business representatives from the GMS Business Forum. The leaders of the six GMS countries are expected to endorse the New GMS Strategic Framework for 2012-2022 and sign a Joint Declaration of the 4th GMS Summit during the summit. GMS leaders will exchange views on continued deepening of the cooperation in nine key sectors -- transport, energy, information and communication, environment, agriculture, tourism, human resources development, trade facilitation and investment later in the day. The summit will also endorse a series of important documents on achievements of cooperation including those in agriculture, environmental conservation, construction of GMS Information Superhighway and GMS cargo transport. The Greater Mekong Subregion Economic Cooperation Program started from 1992 by the six countries sharing the Mekong River -- Cambodia, China, Laos, Myanmar, Thailand, and Vietnam. The Asian Development Bank initiated the program and acts as GMS\'s coordinator, financing bank and technical supporter. The first GMS Summit was held in Phnom Penh, Cambodia in 2002, the second GMS Summit was held in Kunming, Yunnan Province, China, in 2005 and the third GMS Summit was held in Vientiane, Laos in 2008.