An extensive network of empirical relations has been identified in research on the psychological construct of self-monitoring. Nevertheless, in recent years some concerns have been expressed about the instrument used for the assessment of self-monitoring propensities, the Self-Monitoring Scale. Both the extent to which the measure taps an interpretable and meaningful causal variable and the extent to which the self-monitoring construct provides an appropriate theoretical understanding of this causal variable have been questioned. An examination of reanalyses of studies of self-monitoring, analyses of the internal structure of the Self-Monitoring Scale, and further relevant data suggest that the measure does tap a meaningful and interpretable causal variable with pervasive influences on social behavior, a variable reflected as a general self-monitoring factor. We discuss the evaluation and furthering of the interpretation of this latent causal variable, offer criteria for evaluating alternative measures of self-monitoring, and present a new, 18-item Self-Monitoring Scale.According to theoretical analyses of self-monitoring, people differ in the extent to which they can and do observe and control their expressive behavior and self-presentation (e.g., Snyder, 1979). Individuals high in self-monitoring are thought to regulate their expressive self-presentation for the sake of desired public appearances, and thus be highly responsive to social and interpersonal cues of situationally appropriate performances.Individuals low in self-monitoring are thought to lack either the ability or the motivation to so regulate their expressive self-presentations. Their expressive behaviors, instead, are thought to functionally reflect their own enduring and momentary inner states, including their attitudes, traits, and feelings.A number of hypotheses-concerning, among others, the determinants of specificity and consistency in social behavior, the origins of linkages between attitudes and action, the dynamics of social interaction, and the nature and consequences of conceptions of self-have followed from these basic initial propositions. Research involving a measure of self-monitoring propensities (the Self-Monitoring Scale; for information on its reliability and validity, see Snyder, 1974) has provided empirical support for these and many more hypotheses about the cognitive, behavioral, and interpersonal consequences of self-monitoring (e.g