This study explores the relationship between college graduation rates and student participation and success in Advanced Placement (AP) courses and exams. We reviewed three approaches to examining this relationship: 1) comparing the college graduation rates of AP and non-AP students; 2) comparing the college graduation rate of AP and non-AP students after controlling for students' demographics and prior achievement and the demographics of their high schools; and 3) examining the relationship between percent of students from a given high school graduating from college, and the school's percent of students in Advanced Placement. We conclude that the percent of a school's students who take and pass AP exams is the best AP-related indicator of whether the school is preparing increasing percentages of its students to graduate from college. The importance of AP exam results indicates the need for schools and districts to pay close attention not only to the quality of teaching in Advanced Placement courses but also to improving the academic preparation of students prior to their enrollment in those courses. Appendices include: (1) Cohort Definitions and Descriptive Statistics; (2) Hierarchical Linear Modeling Analysis; (3) Ordinary Least Squares Analysis With School-Level Data; and (4) Differences in College Graduation Rates Compared with Students Not Participating in Advanced Placement. A bibliography is included. (Contains 16 tables, 6 figures and 30 footnotes.)