As an island state located in the middle of the Pacific Ocean, where there is limited opportunity for long-distance driving, Hawaii provides an interesting context in which to study fatigue-related crashes. Data from the Hawaii Crash Outcome Data Evaluation System are used to analyze and map fatigue-related collisions. Injury outcomes of fatigue-related crashes are analyzed by using police crash data, emergency medical service records, and insurance claims records. There are distinct temporal and spatial patterns as well as relationships between fatigue-related crashes and driver characteristics. Recommendations for preventing fatigue-related crashes are developed. Roadway segments where fatigue-related crashes occur are identified as possible sites for various engineering treatments. Temporal and demographic information also can be used to design and implement more effective programs and systems for fatigue-related crashes.