Participants who differed in the extremity of self-definition ("own position") with respect to a given trait (sociability, independence, or patience) made trait and evaluative judgments of behavior stimuli that varied in their descriptive implications for that trait. Across four experiments, individual differences in trait ratings of unambiguous information were mediated largely by differences in Ss' affective reactions to these stimuli rather than by direct use of own position as a judgmental anchor. When the target information was ambiguous, however, own position influenced trait judgments independently of Ss' affective reactions to these stimuli. These latter effects were moderated by either encoding or informational mechanisms. A theoretical framework is presented that accounts for these results and predicts how effects of self-knowledge on judgments of others should vary across different trait dimensions.