Notwithstanding a recent flurry of organizational research on the construct of "situational strength," research on the other side of the coin-"personality strength"-has rarely been conducted in organizational settings, has been scattered across multiple disciplines, has been called different things by different researchers, and has not yet been used to test theoretical propositions paralleling those in recent organizational research on situational strength. In the present review, drawing from several disparate research literatures (e.g., situational strength, personality states, traitedness, cross-situational consistency, scalability, appropriateness, selfmonitoring, interpersonal dependency, hardiness, attitude strength, and self-concept clarity), we (a) define personality strength and contrast it with personality trait, personality strengths (plural), and layperson conceptualizations of the terms "strong personality" and "weak personality," (b) briefly discuss the history of research related to personality strength, (c) identify a common prediction, emanating largely independently from several literatures, regarding the interactive effect of personality traits and personality strength on behavior, (d) articulate three novel predictions regarding the impact of personality strength on within-person situational and