Amir Goldberg Stanford University From the schoolyard to the boardroom, the pressures of cultural assimilation pervade all walks of social life. These pressures of cultural alignment are particularly pronounced in formal organizations. Yet people vary considerably in the capacity to fit in culturally, and their fit can wax and wane over time. Why are some people successful in cultural assimilation, whereas others are not? We argue that to answer this question it is necessary to lift the curtain that separates between the backstage (cognitive) and frontstage (behavioral) dimensions of cultural fit. We theorize that the backstage comprises two analytically distinct dimensions: perceptual accuracy, which is an individual's success in deciphering the cultural code, and value congruence, which is the extent to which an individual's private beliefs and values are aligned with those prevalent among her peers. We further hypothesize that perceptual accuracy matters for normative compliance on the forntstage, whereas value congruence is predictive of a person's self-identification and long-term attachment to the organization. Moreover, we argue that the ability to read the code is a matter of context, above and beyond differences in individuals' preferences or psychological capabilities. That is, we contend that the quality of one's peers, especially these peers' degree of normatively compliant behavior, affects the focal individual's perceptual accuracy and resultant capacity for culturally compliant behavior. To evaluate these ideas, we draw on a mixed-methods research design that includes survey data, eight years of internal email communication, and personnel records from a mid-sized technology firm. We use the tools of computational linguistics and machine learning in two ways. First, we develop a measure of frontstage cultural fit based on the linguistic style that employees use in email communications with their colleagues and validate it using the survey. Second, we transform the cross-sectional measures of backstage cultural fit, which were assessed through the survey instrument, into longitudinal measures. We also take advantage of a reorganization that produced quasi-exogenous shifts in employees' peer groups to recover causal estimates of social influence, that is, of how a focal actor's perceptual accuracy and frontstage behavioral fit changed in response to essentially random changes in the peers to which she was connected. Our findings indicate that while individuals adapt their perceptions in response to their peers‰Ûª behavior, exhibiting a secular increase in perceptual accuracy over time, their values remain mostly stable. As perceptual accuracy increases so does one‰Ûªs level of behavioral alignment. Though a substantial proportion of the variance in frontstage behavioral fit is explained by stable differences between individuals, an equally sizeable amount is explained by differences in individuals‰Ûª networks. Employees whose peers behave compliantly are themselves more likely to exhibit cultural fit in their behaviors. Findings from this investigation shed new light on the relationship between cognition and behavior and the interpersonal transmission of culture.