Federal regulation allows truck drivers to use sleeper berths to accumulate eight hours of off-duty rest in two separate periods. Because sleep disruption may cause fatigue and deterioration of performance, a study was conducted to evaluate the association between sleeper-berth use in two periods and tractor-trailer driver fatality. Using Bureau of Motor Carrier Safety Reports, crashes that resulted in tractor-trailer driver fatality were compared with property damage crashes. After adjusting for confounding variables by logistic regression, tractor-trailer driver fatality was found to be significantly associated with sleeper-berth use in two shifts (odds ratio = 3.05). Statistically significant but weaker associations were found between driver fatality and rural district, night driving, gross vehicle weight of 72,000 pounds or more, single-vehicle collision, intercity trip, and employment on an occasional basis.