This research contributes to progress in comprehension of the construct of opportunism and defection through investigation of some personality correlates of opportunism. It reports the results of 3 studies that aim to explore the relationships between economic opportunism and autonomy, agreeableness, and well-being. The first 2 studies (Ns = 193 and 169) examined the correlation between opportunistic propensity, as measured by an economic opportunism scale with measures of autonomy, control, impersonal orientation, Big Five, and psychological well-being. Consistent with predictions, opportunism was positively correlated with control and impersonal orientations; and negatively correlated with autonomy, agreeableness, and psychological well-being. Study 3 (N = 61) showed that the level of cooperation in a trust game was negatively correlated with control orientation.