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Knowledge of how climate and management influence livestock and perennial grass production is needed to address potential consequences of both increasing climate variability and the need to double animal protein by 2050 to accommodate a growing world population.  Here, we evaluate climatic and management determinants on livestock and grass production using a long-term (70 years: 1939-2008) grazing management study with three grazing intensities (light, moderate and heavy) in shortgrass steppe.  Climatic determinants of seasonal precipitation, but not temperature, were the primary influences on livestock production.  Current year (winter, spring, and summer) seasonal precipitation were all robust positive influences on livestock production across the 3 grazing intensities, whereas prior growing season was consistently a robust negative influence suggesting a poor quality forage feedback of remaining plant material from the prior growing season.  Sensitivity of livestock production to seasonal climatic variability increased with increasing grazing intensity, suggesting the adaptations in management to climatic variability will be most advantageous for producers employing heavy grazing intensities.  Counter to observed seasonal climatic and management effects on livestock production, perennial grass production was consistently influenced across the three grazing intensities by a robust positive influence of summer temperature.  Whereas no seasonal precipitation variables influenced perennial grass production with light grazing, spring precipitation was influential for moderate grazing and winter precipitation for heavy grazing.  Sensitivity of grass production to seasonal climatic variability was lowest with heavy stocking, indicating that this highly dominated Bouteloua gracilis plant community is more stable in terms of production and more resilient with increasing climatic variability.  The apparent contradiction in sensitivity between livestock and perennial grass production to seasonal climatic variability can be partially explained by the differential lag effect time of precipitation on vegetation and livestock production.