"The epistemological debate in behavioral sciences (environmental psycholo-gy, geography, anthropdlogy, etc.) centers around the "humanistic versusscientistic" approaches to knowledge generation. This debate has been inher-ited by the applied, professional fields striving for disciplinary status. Inenvironmental planning and design, knowledge is said to be captured in"normative" (I.e., "planning/design theory/criticism") and "postive" theo-ries (of the sciences). The methodological debate in this particular field re-volves around integration of scientific knowledge into application. One issulfacing the scholar In environmental planning and design in the past threedecades Is the "applicability gap" and the related dichotomy between re-searchers and planner/desilgners or research versus design departments inacademia. The reasons given for this gap fall into three categories: the "two communi-ties" or "ignorance" argument, the relevance or "not aksing the right ques-tion" argument, and the "shortcomings of the design process" argument. Thefirst argument emphasizes the lack of communication and understanding be-tween the two communities (one generates and the other uses knowledge) andreinforces the existing dichotomy, The second argument mirrors the epis-temological debate in the behavioral sciences in that the naturalistic view ofknowledge generation is questioned and characteristics of knowledge relevantfor the management of human systems are investigated. Concepts such aslearning in action and experiential or phenomenological nature of knowledgeare discussed. This line of thinking implies the role planning/designing inknowledge generation while providing little procedrual guidance for its in-tegration. The third argument emphasizes the differences between the re-searchers' view of how the planning/design process should be organized(I.e., along the lines of a rational, informational processing model) versusthe process that materalizes. Shortcomings of this process such as inadequte attention given to programming and tack of post-implementation evaluation,proclude the integration of various theoretical constructs and empirical ev-idence.Recent research in planning and design processes question the applicabilityAad desirability of the rational information processing model. In this paper,the studies describing planning and design as a cognitive, behavioral and so-cial process are reviewed. The use of mental consturcts such as proposi-tions, scripts, and schemata; cognitive and behavioral heuristics, and theargumentative nature of the social discourse during the process are dis-cussed. The role of "worldview" or "style" is emphasized. Their implicationson the form and content of "theory" in an environmental planning and designdiscipline are discussed along with methodological considerations for knowl-edge integration.It is concluded that a much stronger and intentional interaction between theart and science or criticism and research process is necessary to generatepositive knowledge useful and usable in environnietal planning and design."