Assistive technology devices for the blind are portable electronic devices that are either hand-held or worn by the visually impaired user, to warn of obstacles ahead. These devices form a small part of a much wider support infrastructure of people and systems that cluster about a particular disability. Various disabilities, in turn, form part of a greater ecosystem of clusters. These clusters may form about a nucleus of various specific disabilities, such as vision impairment, speech or hearing loss, each focusing on its own particular disability category. Clusters are comprised of teams of therapists, carers, trainers, as well as device manufacturers, who design and produce computer-based systems such as mobility aids. There is, however, little evidence of any real crossover collaboration or communication between different disability support clusters.