Conceptual models have become a major focus of occupational therapy practice and education in the last two decades (American Occupational Therapy Association, Inc., 1973; Hagedorn, 1992; Dutton, Levy & Simon, 1993, Christiansen, 1991a; Reed, 1984; Reed & Sanderson, 1983). These conceptualisations are interpretations of the construct, ‘occupation’. Some conceptual models interpret occupation from the perspective of human function and describe the nature of human occupations (Gilfoyle, Grady & Moore, 1981; Kiehlhofner 1985; Reed, 1984, p. 491). The majority, however, interpret occupation from the perspective of occupational therapy, thereby forming the basis of practice models for intervention (Allen, 1985; Ayres, 1979). Despite the evolution of numerous conceptual models describing both human occupations and occupational therapy no single model has adequately met the range of theoretical, practice, and explanatory demands of the profession (Hubbard, 1991).

One conceptualisation of occupation that has been developing since 1972 (American Occupational Therapy Association, Inc., 1973) has been termed, “occupational performance”. Recently, this has evolved into both a framework which forms Guidelines for Client- Centered Practice (Canadian Association of Occupational Therapists, 1991), a terminology classification system (American Occupational Therapy Association, Inc., 1979, 1989; Dunn & McGourty, 1989), and a curriculum guide (American Occupational Therapy Association, Inc., 1974; School of Occupational Therapy, 1986, 1992). Individual theorists have begun to employ the term to describe the content and process of occupational therapy in different areas of practice (Árnadóttir, 1990; Christiansen, 1991; Dunn & Campbell, 1991; Llorens, 1984a; Mosey, 1981, 1986; Nelson, 1984, 1988; Pedretti & Pasquinelli, 1990). To date, conceptualisations of occupational performance have remained largely interventionist or practice focused (Árnadóttir , 1990; Pedretti & Pasquinelli, 1990; Söderbach & Ekholm, 1993) with little development of the notion of occupational performance as a way to explain dimensions of everyday human occupations.

This article describes an expanded model of occupational performance being developed by the authors, the Occupational Performance Model (Australia). Model development commenced in 1986 when it became clear that existing notions of occupational performance used to structure curriculum content in the Bachelor of Applied Science in Occupational Therapy course at Cumberland College of Health Sciences (now The University of Sydney) required expansion to more adequately reflect both the nature of human occupations and occupational therapy practice. In this article, discussion is limited to outlining the structure of the model by defining the major constructs and presenting a brief statement of the underlying assumptions relative to the nature of human occupational performance. Some aspects of the constructs and assumptions outlined are not new but reflect a synthesis of ideas about the nature of human occupations found in the literature (Meyer, 1922/1977; Christiansen, 1991, Llorens, 1991; Reed, 1984). Other aspects of the model extend these constructs and assumptions to form a new configuration of occupational performance that differs from notions currently in existence. Processes that exist within and between key elements and use of the model to explain occupational therapy practice will not be April, 1997, Monograph 1 2 addressed in this article.