Attachment security is known to have various positive outcomes. Recent evidence, however, suggests that security, especially high levels of it, may also have negative outcomes. Three studies tested this possibility. Studies 1 and 2 showed a linear rather than curvilinear trend between security and positive outcomes, suggesting that even at high levels security correlates with positive outcomes. Study 3, which focused on secure behaviors, found that exhibiting high levels of secure behaviors was related to a higher frequency of negative outcomes. However, dispositional attachment security was negatively correlated with negative outcomes, and engaging in secure behaviors strengthened this correlation. These findings suggest that secure behaviors rather than perceptions associated with attachment security (i.e., working models) may be related with negative outcomes.