This paper describes the relationship of a moderately retarded boy with autistic features to an inanimate object, relates this relationship to his emotional development, and suggests methods for utilizing observations of his behavior with the object for assessment of cognition. The authors suggest that the object differs only qualitatively from a transitional object. Implications for the evaluation of retarded children include the necessity for approaches identical to those used in evaluating intellectually normal children and interdisciplinary assessment with combinations of behavioral and dynamic techniques. Implications for parent counseling, institutional policies, therapeutic practice, psychological assessment, and personality theory are outlined.