This study examined the role of parent expectations and adaptive behavior in predicting outcomes for youth with intellectual disability. The study addresses the following research aims: (1) Describe post-school outcomes and parent expectations for individuals with mild and moderate/severe intellectual disability, (2) Determine the relationship of adaptive functioning and parent expectations to post-school outcomes (i.e., postsecondary education, employment, and independent living) for individuals with intellectual disability, and (3) Compare these relationships to the ones that have been identified in previous research on autism spectrum disorder and determine whether these constructs operate similarly or differently in a sample with intellectual disability. Data from the National Longitudinal Transition Study-2 (NLTS2) was used to address these aims. A sample of students with intellectual disability, but without a co-occurring autism spectrum disorder, were selected for inclusion in the study. Four latent variables were created using data from Waves 1, 2, and 5 of data collection: demographic factors, adaptive behavior, parent expectations, and post-school outcomes. Structural equation modeling was used to test structural models of the relationships between these constructs. Results indicate that post-school outcomes for youth with intellectual disability are worse than outcomes for youth with other types of disabilities overall, and that outcomes for those with moderate/severe intellectual disability are significantly worse than for those iii with mild intellectual disability. Results from structural equation modeling indicate that, for youth with intellectual disability, adaptive behavior is more important than parent expectations in predicting post-school outcomes. The relationship between these variables appears different for those with intellectual disability than for other types of disabilities, such as autism spectrum disorder. Results support the conclusion that adaptive behavior plays a critical role in post-school success for individuals with intellectual disability and that parent expectations alone are insufficient to ensure positive outcomes for youth with poor adaptive skills. Implications for clinical practice and future research are discussed. First and foremost, I would like to thank my advisor, Marc J. Tassé, for his constant guidance and support on this project and throughout my graduate career as a whole. I am also grateful to my committee members, Dr. Susan Havercamp and Dr. Andrew Persch, for their insightful comments and feedback throughout this process. I would additionally like to thank Dr. Persch for graciously allowing me access to the NLTS2 data through his restricted-use license, without which this project would have been impossible. I also extend sincere gratitude to Dr. Anne Kirby, who answered my countless questions about NLTS2 data and has been a wonderful source of support. Thank you to Dr. Robert Cudeck and Nicholas Rockwood for the constant guidance, advice, and encouragement ...