Earlier identification, advancements in hearing technology, and more widespread enrollment in early intervention programs have led to improved speech and language outcomes for many young children who are deaf or hard of hearing (DHH) using listening and spoken language (LSL). One cascading effect of these outcomes is that many young children who are DHH using LSL are not qualifying for special education services during the preschool years. Despite norm-referenced performance often within the average range, the literature shows that these children continue to demonstrate language delays using more ecologically valid assessment practices that could adversely affect equitable access in the classroom. The present study aimed to determine how school-based practitioners are assessing and determining eligibility for preschoolers who are DHH using LSL, as well as the relationship between practitioner perceptions and their implementation of recommended and evidence-based practices. I used a questionnaire with a summated rating scale to gather information from a nationally representative sample of practitioners, consisting of early childhood special education (ECSE) and special education (SPED) teachers, teachers of the deaf (TOD), and speech-language pathologists (SLP). Descriptive and inferential analyses showed that practitioners are consistently following recommended practices for the quantity of developmental assessments used, but the evidence-based quality of those assessments is often lacking, particularly for language assessment. Results indicated that general practitioners might demonstrate limited knowledge of eligibility criteria for hearing impairment, whereas TODs with specialized knowledge are often underused when making these determinations. Preliminary findings from this study could inform policy and practice for assessing preschoolers who are DHH using LSL. [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.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]