A communication aid which incorporates a parser with limited intelligence is under development, and is intended to help individuals with aphasia to communicate. There are three important issues that must be addressed in the design of such a system: language representation (how to represent words, phrases, and topics in a way accessible to a person with aphasia), vocabulary selection (which words, etc., to include in the system), and syntactic and pragmatic defaults (what kind of sentence structures should be included in the parser's generative capacities). This paper explores a methodology for designing an intelligent communication device that pays particular attention to these issues. Much of what is discussed should also be useful for designing conventional communication systems as well.