Livestock guardian dogs (Canis lupus familiaris; LGDs) have been used for centuries to protect livestock, primarily domestic sheep (Ovis aries), from depredation by large carnivores. While previous studies have shown their efficacy, the mechanisms in which LGDs protect livestock have largely remained unstudied. Livestock guardian dogs are often considered to be effective only if they remain in spatial proximity to the livestock they are protecting. We determined space use of LGDs relative to domestic sheep on open-range grazing allotments used by working ranches in the Rocky Mountains area of the northwest United States between August 2012 and October 2016. We determined dynamic space use, measured as proximity of LGDs to domestic sheep, and evaluated if this metric differed by breed, sex, or age. The LGDs and sheep were fitted with global positioning system transmitters to obtain location data that were subsequently compared by the above traits using multiple mixed-effect linear models. We found no differences in proximity to sheep on open range among LGDs for any of the 3 traits. Overall, we did find a temporal effect in that all of the LGDs studied were closer to sheep in early morning hours when sheep moved the shortest distances and predators are most likely to be active. These results suggest any of the breeds tested, along with sex or age of these LGD breeds, will remain in proximity to sheep when properly bonded.