Background: Cognitive Bias Modification (CBM) is a promising treatment for Social Anxiety Disorder (SAD). However, previous randomized trials have not systematically examined the combination of CBM for attention (CBM-A) and interpretation (CBM-I) or the credibility and acceptability of these protocols. Methods: We conducted a randomized, double-blind placebo-controlled trial (N 5 32) to examine the efficacy of a CBM treatment called Attention and Interpretation Modification (AIM) for SAD. AIM comprised eight, twice weekly computer sessions with no therapist contact. During AIM, participants (1) completed a dot probe task in which probes always followed neutral faces when paired with a disgust face, thereby directing attention away from threat and (2) completed a word-sentence association task in which they received positive feedback for making benign interpretations of word-sentence pairs and negative feedback for making negative interpretations. We also assessed participants' perceived credibility of and satisfaction with AIM. Results: Participants receiving AIM reported significantly reduced self-reported (Liebowitz Social Anxiety Scale) symptoms of social anxiety relative to the placebo. These gains were also evident on a behavioral measure (performance on an impromptu speech). AIM met our benchmarks for credibility and acceptability in this community sample, although credibility ratings were modest. Participants reported that CBM-I was more helpful than CBM-A. Conclusions: A combined CBM treatment produced medium-to-large effects on social anxiety. Participants rated AIM as moderately credibly and acceptable. Should these findings be replicated in larger samples, AIM has the potential to be a widely accessible and efficacious treatment for SAD. Depression and Anxiety 28:981-988, 2011.