The literature on student academic success of law students is limited to mostly single institution studies, and as such, a nationwide, multi-institutional empirical study of the factors that predict student academic success is greatly needed by higher education scholars, law school admission officers, faculty, and administrators. This dissertation analyzed what effect, if any, undergraduate GPA and LSAT scores, in addition to environmental variables, has on cumulative law school GPA among full-time third-year law students in the United States responding to the 2008 Law School Survey of Student Engagement. A regression analysis revealed five input measures, one between-college characteristic, and fifteen environmental measures were significant predictors of cumulative law school GPA among third-year law students (n=1,756). The intended outcomes of the dissertation are twofold. First, law school faculty and administrators can use this information to promote student involvement that has been shown through this dissertation to influence students' GPA, which is well known in the legal education environment to be critical in the internship and job search process. Second, future studies of law students and other fields of professional education are encouraged to examine what role, if any, student involvement has on outcomes. [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.]