Nearly half of all new community college students drop out of school before successfully completing a degree or credential. It has been found that the greatest percentage of these "non-completer" students terminate their college careers before entering their second year of attendance. First-year seminars (FYS) have long been believed to be positively associated with an increase in student retention. In the spring of 2010, a large community college in the mid-Atlantic region of the U.S. implemented a new FYS enrollment policy that required all degree-seeking first-time college students to enroll in the course in the first semester of attendance. This research attempted to quantify the impact of student compliance with this policy on second-year retention rates. Using a propensity-score matching method this research estimated the average treatment on the treated (ATT) effect by comparing the second-year retention rate of compliant students with non-compliant students. It was found that there was a statistically significant positive impact on second-year retention associated with enrollment in the FYS in the first semester of attendance. This result was estimated to be a 6.07 percentage-point increase in the likelihood of being retained. This result was in line with both theory and other research that suggested that enrollment in FYS is positively associated with improved retention 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://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]