The new approach put forward by the World Trade Organization, aimed at removing technical barriers to free international trade and the promotion of free competition, have brought metrology and measurement techniques to the forefront. As tariffs have been lowered step by step, emphasis has shifted to technical arrangements, besides legal measures, meant to eliminate non-tariff technical barriers to trade. The common aspect of these technical arrangements is that they provide for the international harmonization of control mechanisms used in production and trade. In this regard, it is necessary that the tests and measurements applied to products be recognized by the country to which the products are marketed. Measurement systems created to assure the recognition of measurements internationally are the foundation of technical arrangements that are of great importance for the removal of technical barriers to trade. Arrangements that are based on mutual recognition of between countries have increased the importance of having well organized national measurement systems.