Students who are over 24 yearsolder than the age deemed "traditional" for higher educationaccount for about one in every three students enrolled in community colleges. Unfortunately, their educational outcomes lag behind their younger peers. A greater understanding of what it means to be an adult student in higher education is a crucial step toward determining how postsecondary institutions, particularly community colleges, can improve adults' experiences and chances of achieving their goals. With the overriding objective of providing guidance to stakeholders about how to strengthen adult students' success and increase college completion, we draw from extant literature to develop a Multidimensional Conceptualization of Adult Students (MCAS). We propose a corresponding set of measures to identify adult students in a community college's student population and to differentiate the gradations of experience, responsibility, and subject sense of adulthood that constitute adult status. We review evidence on adult students' participation in higher education, how their approaches to college tend to differ from younger students, and community college programs and initiatives that aim to improve adult students' outcomes. Finally, we discuss the alignment of the programs and initiatives with adult students' learning needs and with the dimensions of the MCAS.