The making of occupation-based models and diagrams: History and semiotic analysis.

Background.: Models provide a structure for organizing knowledge and facilitating learning and are upheld by occupational therapy as epitomizing the cornerstones of its practice.

Purpose.: This article briefly examines the scientific history of occupation-based model development in the 1950s before addressing the process of conceptual model making in occupational therapy. Using the theory of semiosis, it explains and takes a critical perspective on conceptual model building in occupational therapy.

Key Issues.: Since the surge of development in the mid-1970s, models have grown and undergone some revision. However, while the profession has often contested the definitions of its core terms, it has not challenged the accepted models and diagrams that present the constituents of practice.

Implications.: Examining the processes of conceptual model development from a critical, semiotic point of view foregrounds models in the historico-theoretical literature and brings into scrutiny a model's relevancy in current practice.