NIST works to assure that the U.S. realization of the basic and derived measurement units is consistent with the realization in other nations. NIST Laboratories engage in a number of international activities to support trade and global science, and to promote the international acceptance of U.S. measurement standards.

International Metrology

• International Comparisons Database (ICDB) — Compare the National Metrology Institutes (NMIs) with respect to capabilities, measurements, and measurement standards.

• Inter-American Metrology System (SIM) Technical Committee — Information and Support area for the SIM TC. A cooperation among the 34 members of the Organization of American States in establishing national and regional measurement systems and standards that are accepted world-wide.

• Regional Metrology Organizations (RMOs) — Links to the home pages (where available) of RMOs

• National Metrology Institutes (NMIs) — An alphabetical list of NIST's counterpart laboratories in other nations with contact information and web addresses (when available).

• Calibration and Measurement Capabilities (CMCs) — View published CMCs of National Metrology Institutes (NMIs) with respect to capabilities, measurements, and measurement standards.

• NIST Policies and Positions on Key Comparisons