In relation to social network sites, prior research has evidenced behaviors (e.g., censoring) enacted by individuals used to avoid projecting an undesired image to their online audiences. However, no work directly examines the psychological process underpinning such behavior. Drawing upon the theory of self-focused attention and related literature, a model is proposed to fill this research gap. Two studies examine the process whereby public self-awareness (stimulated by engaging with Facebook) leads to a self-comparison with audience expectations and, if discrepant, an increase in social anxiety, which results in the intention to perform avoidance-based self-regulation. By finding support for this process, this research contributes an extended understanding of the psychological factors leading to avoidance-based regulation when online selves are subject to surveillance.