Studies of organizational culture are almost always based on two assumptions: (a) Senior leaders are the prime determinant of the culture, and (b) culture is related to consequential organizational outcomes. Although intuitively reasonable and often accepted as fact, the empirical evidence for these is surprisingly thin, and the results are quite mixed. Almost no research has jointly investigated these assumptions and how they are linked. The purpose of this article is to empirically link CEO personality to culture and organizational culture to objective measures of firm performance. Using data from respondents in 32 high-technology companies, we show that CEO personality affects a firm’s culture and that culture is subsequently related to a broad set of organizational outcomes including a firm’s financial performance (revenue growth, Tobin’s Q), reputation, analysts’ stock recommendations, and employee attitudes. We discuss the implications of these findings for future research on organizational culture.