The "Model of Competence" has been recently elaborated to help expand our understanding relating to a person's interaction with the environment. Specifically, it seeks to deal with the issues related to the home adaptation (the home layout and equipment) for a person living with motor disabilities. This theoretical model takes into account various characteristics of the person as well as of the environment, by re-grouping six concepts: person, environment, activity, role, competence and handicap situation. The "Model of Competence" is distinct because it includes: (1) both the human and the nonhuman dimension of the environment; (2) personal characteristics other than the strictly physical ones; (3) a clear identification of the interaction between the person and the environment; and (4) a means of operationalizing it via an assessment instrument. This model proposes an innovative approach to the person-environment relation in terms of personalizing accessibility, and thereby offers a new approach to understanding the concept of universal access. It has been developed for research and application, and addresses several disciplines.