The Metric Conversion Act of shiting 1975 (later amended by the Omnibus Trade and Competitiveness Act of 1988, the Savings in Construction Act of 1996, and the Department of Energy High-End Computing Revitalization Act of 2004) designated the metric system as the preferred system of weights and measures for US trade and commerce, and directed federal agencies to convert to the metric system, to the extent feasible, including the use of metric in construction of federal facilities.

It also created the United States Metric Board to assist in the conversion, although the Board no longer exists.

The full text of the law is included below. It looks longer than it really is, because much of the text deals with the US Metric Board.