This paper presents a statistical analysis of commuters' route choice behavior and the influence of traffic information. The analysis is based on a 1992 computer-aided telephone interview survey of Los Angeles area morning commuters. The results underscore the important relationship between the use of traffic information and the propensity to change routes. In addition, important relationships are uncovered relating the influence that commuters' socioeconomic characteristics and the level of traffic congestion they face have on traffic information use and route- change frequency. The results' important implications for advanced traveler information systems (ATIS) development are discussed.