This study presents longitudinal data analysis of 6 years of reading scores on a large-scale statewide performance-based alternate assessment for 214 students who are deaf/hard of hearing and have an additional cognitive disability. Assessment scores were examined by complexity level, within grade-level bands, and individually over time. Results indicated that even though the depth of content knowledge increased over time as defined by test specifications, students generally maintained a stable level of proficiency as determined by the state performance standards. Interpretation of results underscores the importance of a multidisciplinary approach to reading instruction among special educators, teachers of the deaf, and speech-language pathologists to improve outcomes of this population.