Adult students are an important subgroup in higher education. They are returning to school in numbers at higher percentage rates than their traditional counterparts. Between 2000 and 2010, the enrollment of students under age 25 increased by 34%; however, enrollment of students 25 and over rose 42% during the same period. From 2010 to 2020, the U.S. Department of Education projects a rise of 11% in enrollments of students under 25 and a rise of 20% in enrollments of students 25 and over (NCES, 2012). As adult students are enrolling in institutions of higher education for myriad reasons, they are often characterized by the responsibilities they carry outside of the classroom; they have family responsibilities and they have jobs. These responsibilities directly relate to adult students having less opportunity to be engaged in learning activities with the academic institution. Adults don't always have the time to put into their studies and other activities on campus because of responsibilities at home and time spent at work or commuting. One of the ways that institutions gauge how well they are doing with student engagement is with the National Survey of Student Engagement (NSSE). NSSE is an instrument used to capture the impact of the institution on students and their educational activities. Given the growing number of adult students, it is important to know how valid the NSSE instrument is when reporting benchmark measures. This research sought to examine the constructs of the NSSE benchmarks and to determine if they are valid and reliable when applied to adult students. The knowledge, experiences, skills, and attitudes of adult students are different than those of traditional-age students, and institutions that are designing effective practices to serve adult students rely on the NSSE benchmark system to guide their efforts. Faculty and administrators are more apt to take responsibility for student learning and improve the quality of undergraduate education if they believe the assessment data to be true and valid. The outcome of the construct validity measure will aid faculty and administrators when examining their current practices and help to improve services and policies for adult students. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]