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Plants experience variation in natural selection across their range due to differences in biotic and abiotic factors. When adaptive evolution occurs in response to local selective pressures, populations are considered to be locally adapted, and we would expect to observe: 1) differences among populations in phenotypic traits, 2) correlations between these trait values and environmental or other habitat-related variables, and, if reciprocal transplants experiments have been done, 3) higher fitness of local over nonlocal populations in the local�s environment. Focusing on plants native to the Great Basin, we asked how frequently each of these three signatures have been observed in wild populations. We conducted a broad literature search to find published studies that compared phenotypic traits of multiple populations of native Great Basin species in one or more common environments. We located 216 experiments in 170 published studies involving a total of 3650 populations of 124 taxa of forbs, grasses, shrubs and deciduous trees, totaling 326 taxon-unique samples. For each sample, we documented whether each of the three signatures of local adaptation was present, and recorded which traits were involved. Additionally, using published data, we asked which phenotypic traits showed the strongest relationships with mean annual temperature and precipitation. Of the studies suitable for detecting each signature, we found that 95.4% reported population differentiation for at least one trait, 81.4% reported significant trait/environment relationships, and 70.4% reported greater performance of local populations in at least one garden for a fitness-related trait. Results indicate that the prevalence of local adaptation in the Great Basin is similar to results in other systems, with many phenotypic and phenotypic traits varying by environment. Our results indicate that considering local adaptation when selecting seed sources could improve restoration success in this large and increasingly imperiled region.