This chapter advocates the use of naturalistic inquiry as a method for undertaking unobtrusive research in instructional development. The advantages of naturalistic inquiry are listed, and it is suggested that these advantages make this form of research very useful to the field of instructional development. It is argued that both naturalistic inquiry and instructional development are focused towards "real world" problem solving, are predisposed to systematic inquiry, and encourage both long term interaction and the development of interpersonal and analytic skills. It is also suggested that the incorporation of naturalistic inquiry into the sphere of instructional development research will serve to widen methodological horizons, expand the research training of instructional development students, and produce a higher quality of research. (14 references) (Author/EW)