This paper serves as the introductory article for the special issue titled, Internationalization in School and Educational Psychology. The paper begins with a summary of the existing literature about internationalization and describes how there are both similarities and differences in the many proposed descriptions and definitions of internationalization. Possible reasons for advancing internationalization within psychology are described next, including those that are applicable for the subdiscipline of school and educational psychology. The paper also describes the scope of this special issue, why it may be timely for the subdiscipline, and its overall goals (i.e., to promote increased understanding and discussion about internationalization, particularly in the context of school and educational psychology).