Past research has demonstrated that the psychological state of observers influences how they view others. This influence often has been termed “projection.” The current study explores projection in close relationships of cohabiting partners. In Study 1a, structural equation modeling revealed a significant component of projection when spouses reported on the depressive symptoms of their partners. In Study 1b, the same analysis was expanded to include spouses’ reports on a variety of affective states, attitudes, and behaviors of their partners. It was demonstrated that the degree of projection increases with the increase in the magnitude of the correlation between the self-views of the spouses. A cognitive process that accounts for this finding is proposed, along with a view of projection as a heuristic device rather than a bias.