The greater sage-grouse (Centrocercus urophasianus) was once widespread within sagebrush-grassland ecosystems of western North America, but populations declined substantially during the 20th century. Given the ubiquity of livestock grazing within sage-grouse habitat and the lack of rigorous scientific data to inform the debate regarding the effects of spring grazing on sage-grouse populations, we propose a collaborative, 10-year research project on replicate study sites across southern Idaho. This proposed project would experimentally evaluate the effects of spring cattle grazing on demographic traits and habitat characteristics of greater sage-grouse. We will pursue the following 3 objectives that examine the effects of grazing on sage-grouse: 1) Document the effects of spring cattle grazing on sage-grouse demographic and behavioral traits; 2) Document the effects of spring cattle grazing on density and diversity of insects (species common in sage-grouse diets) within sage-grouse breeding habitat; and 3) Document the effects of spring cattle grazing on nest concealment and other vegetation features that contribute to sage-grouse habitat suitability.