The New Zealand Seed Certification Scheme has operated for almost 50 years, 12 as a member of the OECD Herbage and Oil Seed Scheme. The objective is to ensure that seed of high cultivar purity is available to the grower having regard to the criteria laid down for the inspection of seed crops. These include the origin of the seed, paddock history, isolation, a field inspection of the growing crop at the optimum time for the detection of contamination with other cultivars and species and certain specific diseases and weeds. Key words: New Zealand seed certification, field inspection.