Whether it is a confederation, registered union, federal union or supranational body, here is the list of unions of which the country is a member. Singapore is a member of several unions. They are Commonwealth of Nations, International Monetary Fund, United Nations, World Bank, World Trade Organization.

Commonwealth of Nations
Singapore is a member of the Commonwealth of Nations. It was admitted to the Commonwealth on August 9, 1966. The Commonwealth of Nations or Commonwealth is an intergovernmental federation of 53 independent and equal sovereign states, most of which were territories of the former British Empire. The Commonwealth includes some of the largest, smallest, richest and poorest countries in the world, spans five regions and is home to 2.2 billion citizens. The Commonwealth operates through the intergovernmental consensus of member states, organized by the Commonwealth Secretariat. 31 of its members are small states, many of which are island states.

IMF
Singapore is a member of the International Monetary Fund. On August 3, 1966, she joined the IMF as a member. Headquartered in Washington, D.C., the IMF is a 189-country organization dedicated to promoting global monetary cooperation, safeguarding financial stability, and facilitating international trade. The IMF now plays a central role in dealing with balance of payments difficulties and international financial crises. The union is governed and accountable to all 189 member countries. In 2010, the Fund had SDR 476.8 billion (about US$755.7 billion) at its disposal.

United Nations
Singapore is a member of the United Nations. On September 21, 1965, it acceded to the United Nations as a full member state on its founding date. The United Nations, founded in 1945, is an intergovernmental organization promoting international cooperation. The work of the United Nations is guided by the principles contained in its founding charter. It currently consists of 193 member states. The United Nations headquarters are in Manhattan, New York City, with other main offices in Geneva, Nairobi and Vienna. Its aims include maintaining world peace and security, promoting human rights, promoting social and economic development, protecting the environment and providing assistance.

World Bank
Singapore is a member of the World Bank. On August 3, 1966, she became a member of the World Bank Group. The World Bank is an international financial institution that provides loans to developing countries. It's like a cooperative, made up of 189 member countries. These member countries are represented by finance ministers, who are the ultimate policy makers at the World Bank. The official goal of the World Bank is poverty reduction.

World Trade Organization
Singapore is a member of the World Trade Organization. On January 1, 1995, it joined the WTO as a member. The World Trade Organization is an intergovernmental organization that regulates international trade. At the core are the WTO agreements ratified by the national parliaments. It is the only global international organization concerned with the rules of trade between nations. The aim is to support producers of goods and services, exporters and importers in conducting their business. The WTO is concerned with regulating trade between participating countries by providing a framework for negotiating trade agreements and a dispute settlement process aimed at enforcing compliance by participants.