This paper proposes that people with neurological conditions can be successfully supported by smart homes only when their needs and aspirations of the technological interventions are fully understood and integrated in the design. A neurological condition can and does provide a clue to the finished technological design but this alone fails to personalise the system and stands to be rejected by the person who requires the technology. This paper explores the underlying issues of the complexity of this design process when designing for people with neurological conditions, and advances a matrix to facilitate the assessment process to maintain a person-centred design of any system.