An approach to classifying the subject matter of higher education is discussed. It is suggested that higher education is primarily a behavioral phenomenon, although it contains nonbehavioral elements, and it should be studied by other disciplines in addition to the behavioral sciences. To study higher education is to study behavioral patterns such as educational management, resource acquisition and allocation, and instruction. A classification of the subject matter of higher education should begin with a definition of the observed behaviors and then define entities such as students and institutions. Most of the systematic knowledge about higher education has been achieved through the concepts and methods of the behavioral sciences. A subject matter classification should link prescriptive principles with a descriptive knowledge base drawn from the behavioral sciences and other disciplines, which would result in a linkage between theory and practice. Attention is also directed to the need for definitions of higher education and postsecondary education, the similarity of behavior within higher education and organizations, and the need to specify various levels of behaviors (i.e., ranging from the individual to the system). (SW)