The International Seed Testing Association (ISTA) is an international non-profit association of seed testing laboratories and individual seed professionals. ISTA operates under the governance of member governments and diverse economies.

The objectives of ISTA are to develop, adopt and publish standard procedures for seed sampling and testing and to promote the uniform application of these procedures for the evaluation of seed moving in international trade, and to promote research in all areas of seed science and technology.

The International Seed Control Association has members from 82 countries worldwide. There are more than 140 ISTA accredited laboratories worldwide.

The National Seed Control Laboratory of the State Plant Protection Service was granted the status of International Laboratory on 1 October 1996 by decision of the International Seed Control Association. On 17 December 1999, the first ISTA international audit was carried out to assess the laboratory's compliance, which resulted in the NSCL obtaining international accreditation on 9 May 2000 with the right to issue ISTA international seed quality certificates. NSKL is the only seed control laboratory in Latvia with the right to issue ISTA International Seed Quality Certificates, thus providing Latvian seed growers with the opportunity to sell seed material not only in the European Union, but also elsewhere in the world.