ABSTRACTThe South African maize sector has been revolutionised from a system of production with low use of modern technologies to a leading maize producer in the African continent. That transformation is in part attributable to South Africa's investment in the national maize cultivar trials, which have facilitated the adoption and use of maize cultivars that are highly adapted to commercial farmer localities, causing considerable gains in yields. The economic value of the public investment in the trials remains unknown. This study uses experimental yields spanning 1977 - 2012 to attribute the influence of the national maize cultivar trials to maize yield improvement on farmer localities in the Highveld region of South Africa. Using attribution methods, the study estimates that 24.3 kg per hectare of extra maize yields accrued to commercial maize producers because of the national maize trials. The economic value of these investments was found to be R1.4billion (in 2012 currency values). The study estimates that South Africa received R37 of benefit for every rand invested by the Agricultural Research Council (ARC) in the trials.