As universities across the nation turn to online delivery formats for many of their courses, the question of optimal class sizes has become increasingly controversial. This article reviews the current multidisciplinary research available to determine what, if any, guidance on online class size exists. The research to date offers no consensus regarding appropriate student-to-teacher ratios in online courses. The authors propose the use of 3 educational frameworks to guide class enrollment decisions that maintain educational quality: Bloom's taxonomy, objectivist-constructivist teaching strategies, and the community of inquiry model. Further research is recommended to assess student learning outcomes across courses of varying size.