Using Petronio's communication privacy management theory, this study tested the degree to which content relevance and students' comfort with instructor disclosures moderated the association between instructor disclosures (i.e., frequency and appropriateness) and credibility (i.e., competence, trustworthiness, and goodwill) in the college classroom. Participants included 362 undergraduate students from a private university in the Southwest. Hierarchical regression analyses revealed that content relevance moderates the positive association between disclosure appropriateness and all three dimensions of credibility, although this interaction and its effect on instructor goodwill depended upon the frequency of instructor disclosures as well. Likewise, students' comfort with instructor disclosures moderated the positive effects of disclosure appropriateness on perceptions of instructor competence and trustworthiness, but not on goodwill. Among the more important implications of this study is the finding that students' comfort with instructor disclosures moderates the effects of disclosure frequency and appropriateness on perceptions of instructor competence.