This article describes the process used to develop a new measure of college knowledge and the findings from an initial study to examine the measure's construct validity. We employed common test construction (item response theory, classical test theory) and factor analytic (exploratory factor analysis, confirmatory factor analysis) approaches to analyzing the data from 519 graduating high school seniors; these analyses support the construct validity of the measure. We discuss the importance of college knowledge in the college decision-making process and implications for school counseling practice and research.