Individuals with unidentified Reading Disorders are at greater risk of poor learning and social-emotional outcomes. Early identification of Reading Disorders ameliorates the risk of school failure. Researchers link early identification of specific Reading Disorders, such as Dyslexia, to communication deficits. Specifically, toddler expressive vocabulary is associated with later development of Reading Disorders and Dyslexia. The purpose of this study is to discover predictors of expressive vocabulary in order to inform early screenings of toddlers for communication deficits and identify at-risk populations for Reading Disorders. Sixty-nine communication inventories of toddlers at 13 and 15 months of age were analyzed. Results indicate that receptive vocabulary at ages 13 and 15 months predicts expressive vocabulary. [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://www.proquest.com/en-US/products/dissertations/individuals.shtml.]