After more than two hundred years, livestock grazing remains California’s most extensive land use. The ‘Range Ecosystems’ chapter in the ‘Ecosystems of California’ sourcebook provides an integrated picture of the biophysical, social, and economic aspects of lands grazed by livestock in the state. Grazing management differs considerably among the Mediterranean, desert, and montane biogeographical regions of the state. Contemporary models predicting range community responses to grazing emphasize site-specific nonequilibrium dynamics and integrated management goals, which include maintaining biodiversity, controlling invasive plants, managing fuels, and protecting soil, water, and air quality. Because forage resources have become limited statewide, management of public range must now consider impacts on private range. Partnerships between ranchers and rangeland landowners are essential to conserving the extensive landscapes cherished in California.