According to attachment theory, the attachment system is activated to manage thoughts, feelings, and behaviors that stem from potential separation and relational threat. Thus, jealousy provides an important situation in which to examine attachment-style differences. In the present study, 144 individuals currently involved in enduring romantic relationships completed questionnaires regarding their jealousy experience, jealousy expression, and attachment styles. Four major findings emerged. First, those with negative self-models reported experiencing more cognitive jealousy than did those with positive self-models Second, jealous individuals with negative other-models reported feeling fear less intensely, using less relationship-maintaining behavior, and engaging in more avoidance/denial than did those with positive other-models. Third, preoccupieds reported displaying more negative affect and engaging in more surveillance behavior than did those with other attachment styles. Finally, dismissives reported feeling less fear than did secures and preoccupieds, and less sadness than preoccupieds, when experiencing jealousy. Attachment-style dimensions, such as lack of confidence and preoccupation with relationships, were also associated with jealousy experience and expression. These results are interpreted in light of attachment-theory principles.