This assessment was accomplished through a review of previous research efforts and by conducting a survey of over 500 Kansas motorists. 43 signs and pavement markings were evaluated in the survey of Kansas motorists. These traffic control devices consisted of 25 warning signs, 13 regulatory signs, and 5 longitudinal pavement markings. Two self-administered questionnaire-type survey instruments were used in this study. The primary instrument consisted of 43 questions with multiple choice responses. The second survey instrument was a self-administered open-ended questionnaire that required the respondents to record their own explanation of the meaning of each sign.