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Pasture legumes are the best long-term option to increase productivity and profitability from grass-dominated pastures in the sub-humid, sub-tropics and tropics of Australia through improving pasture yield, diet quality and performance of livestock. However, finding legume varieties that are persistent and productive in the long-term for the climatic zone and grazing systems has been challenging. Queensland graziers report that long-term persistence (20 to 50 years) of legumes is their highest priority trait for selecting new varieties. Legume and livestock productivity was a second order priority; other traits such as seasonality of growth, ease of establishment, seed production, and methane reduction potential were considered important but of lower priority. Research funding cycles are typically 3 to 5 years, which means long-term persistence of legume accessions cannot be directly measured before release as new varieties. However, there is a network of old pasture evaluation trial sites in the study area which provide s an important opportunity for selecting persistent varieties. Forty-eight pasture evaluation trial sites that were sown between 1978 and 2008 were inspected across southern and central Queensland to identify legumes that persist ed in the long-term. Most of the sites had been 'abandoned ' as research trials for >10 years and generally incorporated back into the grazing property. The two outstanding genera for long-term persistence were Stylosanthes and Desmanthus with some accessions demonstrating long-term persistence across broad geographic locations. Legume persistence at these legacy trial sites has supported new research. Accessions of legumes were described and collected from old trial sites and evaluated across six new sites in southern Queensland. Five new Stylosanthes varieties have recently been released for commercial production demonstrating better persistence and 40 to 70% higher yields (averaged across trial sites) than the best performing commercially available legume stylo varieties. On-going research is identifying persistent and productive Desmanthus accessions for potential commercialisation as new varieties.