The increased demand on the current highway system has caused transportation agencies to increase scheduling for nighttime work in order to alleviate daytime work zone congestion, especially during peak traffic hours. Although traffic congestion is reduced, safety in nighttime workzones remains a concern among both transportation agencies and contractors. According to the Federal Highway Administration (FHWA), approximately one-half of the fatalities that occurred in workzones nationwide occurred at night. These work zone statistics have received increased attention among agencies to evaluate planning and safety issues concerning the workers and the general public on nighttime workzones. Four separate, but interrelated research studies were conducted between September 2005 - May 2007 to address safety issues in nighttime construction and maintenance projects on highways in Indiana. The first study investigated owner and contractor safety management planning for nighttime construction and maintenance operations, while the second study investigated traffic control planning and implementation procedures for nighttime construction and maintenance operations. The third study investigated the effectiveness of speed control measures on nighttime construction and maintenance projects and the fourth study evaluated the effectiveness of high-visibility personal protective equipment practices.