Although research has shown that attachment anxiety is detrimental to ongoing relationships, less is known about whether and how it affects the earliest stages of relationship initiation. How does attachment anxiety affect an initial interaction with a potential relationship partner? The present investigation explored the interpersonal outcomes associated with attachment anxiety in the context of various relational opportunities, testing a mediational model whereby interpersonal displays characteristic of state social anxiety-social disengagement and manifest anxiety-were proposed as mechanisms of interpersonal failure. In Study 1, participants engaged in speed-dating. In Study 2, participants were videotaped introducing themselves to an attractive, single, preferred-sex confederate who would ostensibly be deciding whether to meet them. In Study 3, participants were videotaped having a semistructured 40-min interaction with an attractive, friendly, single, preferred-sex confederate. Across all 3 contexts, attachment anxiety was associated with negative interpersonal outcomes, mediated by displays of social disengagement (Study 2) and manifest anxiety (Studies 1 and 3). The negative displays and outcomes associated with attachment anxiety were expressed behaviorally as verbal disfluencies and interpersonal awkwardness (Study 3). Overall, attachment anxiety was a robust predictor of interpersonal failure when presented with a relational opportunity. Such failures will reinforce the negative expectations underpinning state social anxiety, making it harder for more anxiously attached individuals to initiate and develop the satisfying relationships that might over time help them overcome their relational insecurity.