Self-concept is one of the most popular ideas in psychological literature. Unfortunately, it is also an illusive and often poorly defined construct. Before attempting to assess self-concept, counseling practitioners or researchers must first clarify for themselves what they mean by "self-concept" and then choose a method or instrument consistent with that definition. Perhaps one of the most important distinctions that differentiates various conceptualizations is whether self-concept is viewed as an overarching, global characteristic of the person, or as a set of self-evaluations specific to different domains of behavior. Self-concept is inherently phenomenological, that is, it refers to the person's own view of self. Accordingly self-concept is almost always assessed through self-report. Commonly used self-report methods, rating scales, checklists, Q-sorts, and free response are described. The following considerations must be kept in mind when assessing self-concept: the person must have a sufficient level of self-awareness; measures require substantial verbal competence; and even children are aware that some responses are more socially acceptable than others. Counselors should use scores very cautiously when working with individual clients. (JBJ)