IS certifications are frequently used measures to alleviate consumers’ concerns or increase trust-worthiness toward service providers. Yet, scholarly work trying to understand the effects of IS certi-fication produces contradictory results. In particular, the diversity of theoretical lenses used renders it hard for researchers to stand on common ground. Utilizing a structured review of IS literature, we analyze more than 3100 articles to (1) identify commonly used theories for IS certification, (2) com-pare these theories using the certification ecosystem as conceptual basis, and (3) outline strengths and shortcomings of identified theoretical approaches. We contribute to the existent body of knowledge by presenting theoretical lenses in a structured way as well as evaluating their suitability in the context of IS certification. Our results suggest that some theories are well suited (e.g., Signal-ing Theory), yet researchers need to control for missing antecedents and avoid fragmentary use of theories. Further, we encourage researchers to draw on the Elaboration Likelihood Model and Cue Utilization/Consistency Theory as valuable, though underutilized theoretical lenses. Eventually, we suggest that future research should develop an integrated theoretical model since, according to our results, a blended theoretical lens may be most valuable to understand and predict the effectiveness of IS certification.