Numerous researchers have noted that, instead of response sets or styles, most social desirability scales seem to measure personality traits instead. In two studies, we investigated the substantive interpretation of the Balanced Inventory of Desirable Responding in terms of the HEXACO model of personality. Because of its focus on honesty and integrity, the Impression Management (IM) scale was hypothesized to be mainly related to HEXACO Honesty-Humility. In the main study among 1,106 students and well-acquainted others (friends, family, or partners), positive self-other agreement correlations were found for both IM (r = .45) and Self-Deceptive Enhancement (SDE; r = .34), supporting a trait conception of IM and SDE. In both self- and other ratings, the most important predictors of SDE were (low) Emotionality, Extraversion, and Conscientiousness. IM was associated with Conscientiousness and Agreeableness, but Honesty-Humility was by far its most important predictor. In a subsample (n = 465), Honesty-Humility and IM were unrelated to GPA.