The purpose of this paper is to call attention to certain important aspects of self-concept which have been largely neglected in behavioral science research literature. Self-concept is defined as the totality of the individual's thoughts and feelings with reference to himself as an object. Three broad areas of self-concept are discussed. The first area, the extant self-concept, includes the content of the self, the relationship among the parts, the ways of describing the parts and the whole and the boundaries of the object, or the ego-extensions. Previous self-concept research on these structures indicates a general neglect of ordering self-concept traits in hierarchical order. The second aspect of self-concept is the desired self. Meaningful aspects of self-concept largely neglected in research in the area of the desired self include individual acceptance or nonacceptance of a personal characteristic, the dimensions of self-consciousness, self-confidence, and self-values. The third section discusses the social or presenting self. It purports that the tendency of most research is to confuse the presenting self with the extant self-concept. (Author/DB)