This paper discusses the development of a criterion-referenced assessment measure for both written English and American Sign Language (ASL) that can be used with deaf elementary through secondary students. The measure is presented as well as the results of a trial use. Developed by the Cleary School for the Deaf, the Cleary Language Assessment (CLA) uses non-verbal stimuli, such as silent films, to gather written and signed samples (which are videotaped). These samples are analyzed both objectively and subjectively. The objective analysis measures seven components of the English language (punctuation, grammar, capitalization, vocabulary, sentences, paragraphs, and word usage), while the subjective analysis measures the organizational cohesiveness of written language. The ASL component of the measure consists of a checklist of ASL skills. The scores of 32 elementary and high school students who took the CLA during the 1990-91 academic year are appended, along with a discussion of the validity of the measure. (MDM)