A job analysis was conducted to define knowledge important for entry-level teachers of students with language impairments. The results will be used to guide the development of new test content specifications for the Praxis™ Series Teaching Speech to Students with Language Impairments (TSSLI) assessment. A draft domain was constructed from various national and professional organization standards, articles, and textbooks used in the field. A national advisory committee (NAC) of 11 teachers, speech language pathologists, college faculty, and one supervisor reviewed and modified the draft domain to reflect the knowledge they believed was important for safe and effective practice and needed at time of entry into the profession. The revised domain consisted of 57 statements clustered within four major categories:(a) Foundations of Speech-Language-Hearing Development Impairments; (b) Identification and Assessment of Communication Impairments; (c) Planning and Managing the Learning Environment; and, (d) Legal, Ethical, and Professional Aspects of the Job. Survey responses of 2,715 educators provided independent evidence of the importance of the domain. Respondents judged each knowledge statement on a scale ranging from 1 (not at all important) to 5 (extremely important). Forty-seven knowledge statements had mean ratings above 3.50 in the aggregate sample and for subgroups containing more than 30 respondents. These results indicate that the 47 statements may be considered appropriate for guiding the development of new test content specifications for the Praxis TSSLI assessment.