A core assumption of personality is that individuals are characterized by qualities that are relatively invariant across situations and over time. Historically, this led to a search for evidence of high consistency in a person's behaviour across diverse situations. Empirical studies have shown, however, that, at least for behaviours of interest to social and personality psychologists, cross‐situational variability, rather than consistency, is in fact the norm, creating years of debates and crises regarding the nature of personality consistency. Our goal has been to resolve these crises by showing that people have stable ‘behavioural signatures’ visible in patterns of cross‐situational variability rather than consistency, and by suggesting an alternative conception of personality coherence based on the emerging general model of cognitive–affective processing of social information. In this conception, an individual is characterized by the cognitions and affects that are accessible, and the features of situations that activate them. The personality system, however, is not just a list of such accessible thoughts and feelings, but, rather, a dynamic network of functional relations that guides and constrains their activation. The present paper shows how such a system will produce a characteristic, and stable, pattern of variation of its behavioural output as a function of specific features of situations, and how these signatures of personality reflect the stable system that generates them. Copyright © 2000 John Wiley & Sons, Ltd.