Elimination of IDD is a most important health and social goal. Iodine deficiency at critical stages during pregnancy and early childhood results in impaired development of the brain and consequently in impaired mental function. While a variety of methods exists for the correction of iodine deficiency, in practice the most commonly applied is universal salt iodization the addition of suitable amount of potassium iodate to all salt for human and livestock consumption. There are three major components of a sustainable programme to eliminate IDD: political support, administrative arrangements, and assessment and monitoring systems. The provision of scientific data implies measuring progress to demonstrate that adequate amounts of iodine are reaching the target population. This requires the selection of appropriate indicators of both the salt iodization process and its impact. The iodine content of salt is the indicator of the salt iodization process. This is accurately measured by titration. The most important place for monitoring salt iodine levels is at the production level. This is the responsibility of the producer, with verification by an external body such as the national food standards authority. Rapid test kits give a qualitative estimate of whether iodate is present in salt, but cannot reliably determine.