The paper reports on a case study of the language environments of two severely involved, non-oral cerebral palsied preschoolers. Observation of interactions, comprehension development, acquisition of productive signals and of use of supplementary communicative devices revealed deviances in language directed to severely multiply physically handicapped (SMPH) children which may have a profound effect on the developing communicative systems of these children. Peculiarities were noted in lexical and conceptual input, control of the interaction, (relationship of self to others) function of the interaction, and exposure to speech events. It is noted that there are "holes" in the lexical input of the language adults direct to SMPH children. One possible explanation for the gap in conceptual/lexical input may be adults' disinclination to "go half-way" with non-oral SMPH, their seeming lack of enthusiasm for an extensive acceptance of different levels of participation. The interactions of SMPH children are predominantly initiated and terminated by others, interactions seldom allow the SMPH student to express preferences or choices, and SMPH children are largely excluded from the conversational aspects of events. Findings stress the importance of the quality of adult-SMPH child interaction for the child's communicative progress. (CL)