25 airports have a connection with the local rail transit system, but each is unique. Variables such as network size, train frequency, type of airport station, time, and cost vary by airport. Both airport passengers and planners should have a technical basis of selecting which system is the most useful, efficient, and reliable. To date, there have been no scoring procedures created to rank the airports in order of quality of connection. This thesis analyzes rail transit accessibility for all 25 airports (3 of which have 2 separate transit systems) by investigating 8 characteristics, 3 of which are market factors and 5 of which are system factors. The 5 system factors are travel time difference between car and train, transit cost difference between car and train, airport/transit connection type, network size, and train frequency. The 3 market factors are rail transit mode share, business traveler percentage, and low-cost carrier percentage. A scoring system was then developed and each airport's characteristics were inputted. The airports were scored using three different methods and were subsequently evaluated to understand why airports received the scores they did. This evaluation led to a better understanding of airport transit best practices. The scoring system was used again to evaluate an airport (Washington-Dulles) undergoing radical changes to understand by what factor a score can improve. A "top 10" list of airport transit connections was produced with JFK coming in first. This method is a starting point for developing a robust system to evaluate transit connections to airports. / Master of Science