Using the Delphi method, this study was designed and undertaken due to a lack of existing research regarding key factors that support successful transitions of TWI students from elementary to middle and high school. The purpose of this study was first to identify the opinions of experts and practitioners in the field of TWI programs on key factors that support these transitions, and then to rate the importance of these factors as they pertain to the student’s designation as a dual language student. Subsequently, based on the results from the panel of 16 experts, the researchers investigated how a group of parents ranked the key factors that the expert panel identified as most and least important for successful transitions. The experts identified teacher qualification, curriculum and program planning, communication among school personnel, and administrative support as the most important factors to support student transitions. The group of parents rated the factors determined to be important by the panel highly, generally more highly than the expert panel itself, but parents also deemed