This research assumes that systematic and systemic change are two components in instructional design (ID)--not dichotomous terms, but two sides of an interconnected dual structured system. Specifically, this paper examines the difference between systemic thinking and systematic thinking, the ideal mental model (dual structured systems) for ID, and the benefits from this mental model. The introductory section discusses the need for a dual structured instructional systems approach. An overview of the problems relating to systematic and systemic is then presented that covers the following topics: (1) dictionary definitions of the two terms; (2) different approaches of the two terms in the field of instructional systems design (ISD); (3) distinctions based on hard systems (typical tasks, step-by-step procedures) vs. soft systems (typical events, heuristic problems); (4) the conceptual model of dual structured instructional systems; (5) some guidelines for increasing systemic thinking, including the ability to see the problem as holistic, to set goals in a given problem situation, to link possible resources in terms of goals, and to drive a tentative result; and (6) the benefits of the dual structured systems approach. It is concluded that both systematic and systemic approaches are necessary for ID. (MES)