This article provides a summary of research related to the groupthink theory. The review includes case studies, experimental studies, literature reviews, example applications, and proposed modifications to the groupthink theory. Groupthink has been applied to a broad spectrum of group settings and is seen as a major factor in many poor decisions. Despite close to 40 years of the existence of the groupthink theory, experimental studies are limited with only a few of the model‘s 24 variables adequately tested. Testing limitations, and their mixed experimental results, lead to a wide diversity of perspectives regarding the model. Some conclude groupthink is no better than a myth, while others believe it is a brilliant construct. One recommendation is to address the ambiguity of the model; implementing previously proposed modifications (identified in this article) would achieve this objective. A further recommendation is to increase focus on testing groupthink prevention steps.