A job analysis was conducted to define knowledge/skills important for entry-level secondary mathematics teachers. The results will be used to guide the development of new test content specifications for The Praxis Series Mathematics: Content Knowledge assessment and the Praxis Series Mathematics: Proofs, Models, and Problems, Part 1 assessment. A draft domain was constructed from Common Core State Standards for Mathematics, existing test specifications, data from previous job analysis results, and the National Council of Teachers of Mathematics: Standards for Grades 9–12. A national advisory committee (NAC) of secondary mathematics teachers and college faculty, reviewed and modified the draft domain to reflect the knowledge/skills they believed were important for safe and effective practice and needed at time of entry into the profession. The revised domain consisted of 114 statements clustered within nine major categories: (a) Number and Quantity, (b) Algebra, (c) Functions, (d) Geometry, (e) Statistics and Probability, (f) Discrete Mathematics, (g) Calculus, (h) Mathematical Processes, and (i) Pedagogy. Survey responses of 436 mathematics educators provided independent evidence of the importance of the domain. Respondents judged each knowledge/skill statement on a scale ranging from 1 (not at all important) to 5 (extremely important). A total of 101 knowledge/skill statements had mean ratings above 3.50 in the aggregate sample and for subgroups containing more than 30 respondents. The results indicate that these 101 statements may be considered appropriate for guiding the development of new test content specifications for the Praxis™ Mathematics: Content Knowledge assessment and the Praxis Mathematics: Proofs, Models, and Problems, Part 1 assessment.