The authors used a multiple-baseline-across-behaviors (i.e., word lists) design to evaluate a computer-based flashcard intervention on automatic sight-word reading in a 4th-grade student with moderate to severe intellectual disabilities. Immediately after the intervention was applied to each of three lists of sight words, the student made rapid gains in her ability to read those words within 2 s. Approximately 8 weeks after the final intervention session, evidence for maintenance and generalization were collected when the student read words learned during the computer-based flashcard procedure that were hand written on index cards, as opposed to displayed on the computer screen. The authors' discussion focuses on the contextual validity (e.g., sustainability, efficiency) of this computer-based intervention. (Contains 1 figure.)