Two varying types of multiple stimulus without replacement preference assessments (MSWO) were conducted with three 21-year-old participants with low-functioning autism. The first preference assessment was parent-led. This was done by using a revised version of the RAISD, a parent interview tool, to gain the top ten items the parent viewed as being most reinforcing to their child. The experimenter then utilized those 10 items to conduct the multiple stimulus without replacement preference assessment. All three participants were also given a standard multiple stimulus without replacement preference assessment utilizing 10 generally common used reinforcing items that are typically available in a classroom setting. Upon yielding the results of each type of preference assessment, an alternate treatment design was utilized to determine reinforcing effects of the varying preference assessment results. A baseline phase occurred where participants completed a matching-to-sample file folder task, that they have all shown 100% competency with in the past, to record the duration and accuracy it took the participants to complete the activity while receiving no reinforcement. Duration and accuracy for the matching-to-sample file folder activity were then compared to determine if they would increase their speed and accuracy when presented the opportunity to gain the parent-led and standard preference assessment result's reinforcer upon completion. Results showed students displayed shorter durations for both types of preferences, however slightly favored the teacher-led assessment. Accuracy was generally the same for baseline and both types of preference assessments.