This study compared the use of delivering single instruction versus varied instructions when teaching three children diagnosed with autism spectrum disorder (ASD) new expressive labels. The present investigation utilized an adapted alternating treatment design nested into a multiple probe design, to teach participants to expressively label pictures of cartoon characters using either single instruction or varied instructions. The goal of this study was to evaluate the acquisition, effectiveness, and efficiency of the two different procedures for each participant. The results demonstrated that while students learned all targets in both conditions, skill acquisition rates were slightly higher for the majority of participants using varied instructions. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]