Thailand is a country located in Southeastern Asia bordering the Andaman Sea and the Gulf of Thailand. Neighboring countries include Burma, Cambodia, Laos, and Malaysia. The geography consists of a mountain range in the west and a southern isthmus that joins the land mass with Malaysia. The government system is a constitutional monarchy. The chief of state is the King and the head of government is the Prime Minister. Thailand has a mixed economic system in which there is a variety of private freedom, combined with centralized economic planning and government regulation. Thailand is a member of the Asian Pacific Economic Cooperation (APEC), Association of Southeast Asian Nations (ASEAN), and Bay of Bengal Initiative for MultiSectoral Technical and Economic Cooperation (BIMSTEC).