This study examined the effects of mindfulness-based stress reduction (MBSR) on the brain–behavior mechanisms of self-referential processing in patients with social anxiety disorder (SAD). Sixteen patients underwent functional magnetic resonance imaging while encoding self-referential, valence, and orthographic features of social trait adjectives. Post-MBSR, 14 patients completed neuroimaging. Compared to baseline, MBSR completers showed (a) increased self-esteem and decreased anxiety, (b) increased positive and decreased nega-tive self-endorsement, (c) increased activity in a brain network related to attention regula-tion, and (d) reduced activity in brain systems implicated in conceptual-linguistic self-view. MBSR-related changes in maladaptive or distorted social self-view in adults diagnosed with SAD may be related to modulation of conceptual self-processing and attention regulation. Self-referential processing may serve as a functional biobehavioral target to measure the effects of mindfulness training. S ocial anxiety disorder (SAD) is a common and frequently debilitating condition character-ized by intense fear of evaluation in social or performance situations (Jefferys, 1997; Kessler et al., 1994). SAD has an early onset (Otto et al., 2001) and regularly precedes other anxiety, mood, and substance abuse/dependence disorders (Lampe, Salde, Issakidis, & Andrews, 2003; Matza, Revicki, Davidson, & Stewart, 2003). SAD is associated with significant distress and functional impairment in both work and social domains (Lochner et al., 2003; Rapee, 1995; Schneier et al., 1994) and typically persists unless treated (Clark & Wells, 1995). The early onset of SAD magnifies its impact, including increased school dropout (Van Ameringen, Mancini, & Farvolden, 2003), poor social integra-tion, and increased comorbid psychopathology (Lampe et al., 2003; Matza et al., 2003; Randall, Thomas, & Thevos, 2001).