The National Education Act of the year 1999, amended (2nd Issue) in 2002 obliges the government to provide education to make Thai people to become full development in all aspects: physical and mental health; intellect; knowledge; morality; integrity; and desirable way of life so as to be able to live happily with other people. It also states that educational provision shall be based on organizing the system, structure, and process of education on various principles such as: (1) unity in policy and diversity in implementation; (2) decentralization of authority to educational service areas, educational institutions and local administration organizations; and (3) setting of educational standards and implementing system of quality assurance for all levels and all types of education.
Therefore, it was necessary for the government to set up a neutral national organization to monitor and evaluate the outcomes of education in order to find out whether the quality and equality of education for the people in general reach expected standards or not.
The National Institute of Educational Testing Service (Public Organization) or NIETS in English for short was established as a public organization to make it works effectively by means of making use of its resources and personnel at its maximum. It has freedom and does not rely on any educational organizations; therefore, it can remain its neutrality. It is an institute that can set up its own principles, policies, measures, targets, administrative structures and working plans in accordance with the government and any concerned organizations. It has its own personnel, finance, auditing and a systematic and effective evaluation sectors in order to make the objectives of its existing fulfilled, namely, to manage and administrate education, to conduct research studies, to give services on educational testing and measurement continually, and to be a center working cooperatively on educational testing at national and international levels.