The World Bank Group (WBG) is a family of five international organizations responsible for providing finance and advice to countries for the purposes of economic development and eliminating poverty. The Bank came into formal existence on 27 December 1945 following international ratification of the Bretton Woods agreements, which emerged from the United Nations Monetary and Financial Conference (1 July – 22 July 1944). Commencing operations on 25 June 1946, it approved its first loan on 9 May 1947 ($250m to France for postwar reconstruction, in real terms the largest loan issued by the Bank to date). Its five agencies are:

• International Bank for Reconstruction and Development (IBRD)
• International Development Association (IDA)
• International Finance Corporation (IFC)
• Multilateral Investment Guarantee Agency (MIGA)
• International Centre for Settlement of Investment Disputes (ICSID)

The term "World Bank" generally refers to the IBRD and IDA, whereas the World Bank Group is used to refer to the institutions collectively. blank">"About Us", wordbank.org, accessed May 30, 2007.

The World Bank's (i.e. the IBRD and IDA's) activities are focused on developing countries, in fields such as human development (e.g. education, health), agriculture and rural development (e.g. irrigation, rural services), environmental protection (e.g. pollution reduction, establishing and enforcing regulations), infrastructure (e.g. roads, urban regeneration, electricity), and governance (e.g. anti-corruption, legal institutions development). The IBRD and IDA provide loans at preferential rates to member countries, as well as grants to the poorest countries. Loans or grants for specific projects are often linked to wider policy changes in the sector or the economy. For example, a loan to improve coastal environmental management may be linked to development of new environmental institutions at national and local levels and the implementation of new regulations to limit pollution.

The activities of the _IFC and MIGA include investment in the private sector and providing insurance respectively.

The World Bank Institute is the capacity development branch of the World Bank, providing learning and other capacity-building programs to member countries. Two countries, Venezuela and Ecuador, have recently withdrawn from the World Bank.