This article aims to revisit and to adapt the Norman's theory of action by focusing on the design of interactive systems for disabled people. The background section demonstrates that there is a need to include all the stakeholders involved in the environment of the disabled person in the design process, constituting his or her ecosystem. Then the adaptation of the Norman's theory action, considering explicitly the ecosystem is justified; examples of the both role of the disabled people and members of his/her ecosystem are given for the seven components of Norman's model. Two cases studies are after presented to illustrate the crucial role of the ecosystem in case of assistive interactive system design. The benefits of taking into account the ecosystem in the design of interactive systems for disabled persons are discussed. The article ends with a conclusion and research perspectives.