The document of Annual Report 2011 of  National Housing Authority of Thailand. National Housing Authority, a state enterprise under the Ministry of Social Development and Human Security, was established on February 12, 1973, in compliance with the National Executive Decree No. 316. It currently operates under the National Housing Authority Act, B.E. 2537, and the National Housing Authority Act, B.E. 2550 (the amendment Act). NHA was created by merging related government agencies that provided affordable public housing for the country: Housing Welfare Division under the Department of Social Welfare, Office of Housing Welfare, Housing Welfare section of Government Housing Bank, and Office of Slum Improvement under Bangkok Metropolitan Administration.