The Test of Early Mathematics Ability--Third Edition (TEMA-3) is a norm-referenced parallel forms test intended to identify the level of mathematical ability for children aged 3 years 0 months through 8 years 11 months. According to the authors, the instrument can also be used as a criterion referenced or diagnostic tool for older students who are having difficulty in mathematics. Additionally the TEMA-3 can be used to identify those children who are significantly ahead or behind their peers in mathematical thinking, identify specific strengths and weaknesses in mathematics, document progress in learning arithmetic, and provide information to guide instructional practices. The TEMA-3 was designed to measure a child's overall mathematical knowledge. Specifically, the test measures informal (e.g., numbering and calculation) and formal (e.g., written representation of numbers) mathematics. This article provides a general description of TEMA-3 and its technical adequacy. An evaluation of TEMA-3 is also discussed.