This article describes accident characteristics on freeway facilities where work zone traffic control procedures were of a high standard in terms of current state-of-the-art. Data is based on the results of a 3-year study of traffic control needs at freeway work zones. The study is summarized with emphasis on accident characteristics. The two most disruptive types of work zone traffic control were crossovers and lane closures. The study revealed the following: (1) The high involvement of trucks at night in accidents at crossovers is an indication that, for them at least, the driving task is more demanding here than at other work-site zones or on the Turnpike in general, resulting in more driver errors; and (2) The high injury rates corresponding to accidents in the bi-directional zones suggest that driver errors in the zone have more severe consequences than driver errors at other sections within work sites or on the Turnpike in general.