In 2005, the New York State Department of Transportation authorized the first-time use of semipermanent, high-mast, pole-mounted luminaires to illuminate nighttime road work construction and maintenance. This approach was used along a 3-mi stretch of Interstate 90 in Albany, New York, as an alternative to portable light towers. The performance of the high-mast lighting system is assessed according to the criteria of construction work quality and safety and visibility for workers and drivers. The high-mast lighting system was found to have met lighting performance specifications. Field measurements and an analytical comparison of the high-mast lighting with the portable light towers suggested that the high-mast lighting system provided sufficient illumination for performing maintenance and construction activities at the site, with few shadows and relatively low glare, thereby increasing visibility of hazards and improving performance of visual tasks for both workers and motorists. On the basis of these analyses, the high-mast lighting system should provide a higher level of safety than the portable light towers for the construction workers and for the drivers traveling through the construction zone for this project. The high-mast lighting system should also reduce the risk of injury to construction workers during high-exposure times when they would be setting up and removing portable lighting equipment. Other considerations, such as the implications for conditions of wet pavement and mesopic vision, are explored.