Self-Knowledge Development Theory (SKDT) by Weinstein and A. Alschuler (1985) is a structural developmental theory positing four stages in the development of self-knowledge. The Experience Recall Test-2 (ERT2) is described, which is the most recent instrument developed for assessing the SKDT. Self-knowledge is defined as the ability to describe internal experiences as fully as possible, to anticipate internal responses as precisely as possible, and to manage that experience as intentionally and effectively as possible. Four invariant, hierarchical stages are present in the growth of these abilities: (1) elemental; (2) situational; (3) pattern; and (4) transformational. The theory is pertinent to theoreticians and researchers interested in human development and to practitioners interested in promoting the growth of these abilities. It assists practitioners in understanding and differentiating clients, setting manageable goals, and selecting and sequencing interventions. The ERT2, which can be administered in groups, is designed to elicit the highest level of self-knowledge of which an individual is capable. The instrument includes a memory scan, a description of a significant event, and questions about that event. Further study of the ERT2 and its coding manual is needed to establish reliability. The ERT2 and associated instructions are appended. (TJH)