This article reviews the "Wechsler Individual Achievement Test-Third Edition" (WIAT-III), a newly updated individual measure of academic achievement for students in Pre-Kindergarten through Grade 12 (age 4 years, 0 months to 19 years, 11 months). Suitable for use in educational, clinical, and research settings, the stated purposes of the WIAT-III are to identify student academic strengths and weaknesses, inform special education eligibility and/or placement decisions, inform the diagnosis of specific learning disabilities, and to aid in the design of instructional objectives and interventions. The WIAT-III is classified as a Level B measure, and may be administered and interpreted by psychologists and nonpsychologists who have undergone formal training in standardized psychological or educational testing. The WIAT-III includes 16 subtests; however, examiners can choose to administer individual subtests, a selection of subtests, or all subtests, depending on the grade level or the presenting difficulties of the examinee. These subtests combine to form seven composites: Oral Language, Total Reading, Basic Reading, Reading Comprehension and Fluency, Written Expression, Mathematics, Math Fluency, and a Total Achievement Score. (Contains 1 table.)