Recent studies by Fogg and his colleagues have defined a new psychological construct called Web credibility. It describes the principal dimensions which lead people to believe (or not) online information. In this framework, the factorial structure of Web credibility was explored in a sample of 152 Italian students of psychology who were Internet users, using a questionnaire. A consistent four-factorial structure emphasized crucial aspects of Web credibility, namely, Inaccuracy, Efficiency, Social Validation, and Commercial Features. Such results seem in line with Fogg's theoretical model; however, further research is required to identify dimensions of this construct.