For more than six decades, Swiss grassland farming has been successfully relying on a system of elite grass-clover mixtures, the so called ‘standard mixtures’. Today, leys are almost exclusively seeded with grass-legume mixtures and about 80% of these mixtures are traded as standard mixtures. The four keyfactors for this outstanding success are: (1) an unambiguous system offers forty-six mixtures in a broad range from intensive forage production to improvement of biodiversity. Grouping of individual mixtures to main types enables an easy choice of the appropriate mixture. (2) Scientific development of seed mixtures in multi-site, multi-annual field experiments taking into consideration the breeding progress by the exclusive use of recommended varieties enables optimised recipes. (3) Extensive practical testing of the most promising candidate mixtures on-farm ensures robustness and feasibility. (4) Collaboration with extension services, the seed industry and the Swiss Grassland Society anchors the system in practice manifested by a quality label awarded by the Swiss Grassland Society.