  The involvement of the ecosystem or social environment of the disabled user
is considered as very useful and even essential for the human-centered design
of assistive technologies. In the era of model-based approaches, the modeling
of the ecosystem is therefore to be considered. The first version of a
metamodel of ecosystem is proposed. It is illustrated through a first case
study. It concerns a project aiming at a communication aid for people with
cerebral palsy. A conclusion and research perspectives end this paper.
