Both attitudes and traits have served as within-person constructs intended to permit the prediction of later behavior. Despite this similarity, research in the two domains has tended to progress in a relatively independent fashion. A number of parallels between the attitude and trait literature are noted with regard to definitions of the constructs and their utility as predictors of behavior. Parallels with respect to the identification of variables that moderate the attitude-behavior and trait-behavior relation are also discussed, as are similarities in the potential processes by which attitudes and traits guide behavior. It is concluded that the parallels are so extensive that research in each domain would benefit from an increased exchange of theory, methods, and findings.