This paper focuses on the domain of concern part of a professional model presented by Mosey in her book Occupational Therapy: Configuration of a Profession (Raven, 1981). Based on additional review of the literature, I suggest two principal alterations.

1. A change in core versus parameter. “Human occupation” replaces “occupational performance” and is presented as the core of the domain of concern because this is the focus of occupational therapy practice; the “performance components” defined here as “competence components” actually serve as a parameter of practice.

2. A reconceptualization of two parameters: “time” and “cultural environment.” Time should be considered a separate parameter, including categories of time practice, balance of activities over time, and time perspective. Cultural environment is perceived as a parameter that is composed of four categories: the symbolic, social, physical, and natural environments.

This paper emphasizes the interrelatedness of all parts of the model and points out the qualitative differences between the parameters.