Highway maintenance and construction activities are oftentimes performed in a travel lane, median, or shoulder adjacent to vehicles traveling at relatively high speeds and in close proximity to the workers. Work zone traffic control efforts include safety measures for the workers that typically include multiple traffic control devices. However, worker and motorist safety continues to be a concern. Current traffic control capabilities for short duration work zones can be improved in order to increase the protection of workers and reduce the effect of the maintenance activities on the travelling public. A recent advancement in work zone safety is a mobile barrier system that consists of a motorized tractor/trailer combination and provides complete isolation of the work area. This paper presents research conducted to investigate the impacts of a mobile barrier on vehicles traveling adjacent to the mobile barrier and maintenance work zones. The study findings show that vehicle speeds are higher with the mobile barrier present than without the mobile barrier, indicating greater mobility as a result of faster travel times through the work zone. The presence of a mobile barrier resulted in lower speed reduction from the beginning to the end of the work zone. This positive impact on vehicle movement through the work zone complements the increased worker safety provided by the mobile barrier.