Research Findings: The focus of this study was to construct and validate 12 brief early numeracy assessment tasks that measure the skills and concepts identified as key to early mathematics development by the National Council of Teachers of Mathematics (2006) and the National Mathematics Advisory Panel (2008)-as well as critical developmental precursors to later mathematics skills noted in the Common Core State Standards (2010). Participants were 393 preschool children ages 3 to 5 years old. Measure development and validation occurred through 3 analytic phases designed to ensure that the measures were brief, reliable, and valid. These measures were 1-to-1 counting, cardinality, counting subsets, subitizing, number comparison, set comparison, number order, numeral identification, set-to-numerals, story problems, number combinations, and verbal counting. Practice or Policy: Teachers have extensive demands on their time, yet they are tasked with ensuring that all students' academic needs are met. To identify individual instructional needs and measure progress, they need to be able to efficiently assess children's numeracy skills. The measures developed in this study not only are reliable and exhibit evidence of validity but also are easy to use and can be utilized for measuring the effects of targeted instruction on individual numeracy skills.