Described in this paper is a study of advance warning signs for median crossovers on divided highways. Candidate crossover signs were identified from a literature review, survey of current state practices, and discussions with FHWA personnel. Seven of these signs were selected for further testing in a laboratory study for legibility, understanding, and driver preference. Sixty subjects representing a cross-section of drivers participated in the study: 30 at the Turner Fairbank Highway Research Center in McLean, Virginia, and 30 at the University of Missouri-Rolla, in Rolla, Missouri. Two of the seven signs were word messages and five were symbolic signs. The results from both groups of participants showed that the most appropriate word message sign would appear to be" median crossover". This sign was understood best by the participants to whom it was shown, and" crossover" was the word the majority of participants believed best conveyed the intended meaning. Of the symbolic signs tested, the one found to be the best was that of two median noses. This symbolic sign performed well in tests of legibility and understanding and was the sign least often confused with other signs. It was also the symbolic sign most preferred by the participants and was the simplest of the symbolic designs. The symbolic signs were substantially more legible than the word messages, and the symbolic design of two median noses is recommended to identify median crossovers.