Increasing the effectiveness of two- to four-year college transfer is critical for meeting national goals for college attainment and promoting upward social mobility. Efforts to improve institutional effectiveness in serving transfer students and state transfer policy have been hampered by a lack of comparable metrics for measuring transfer student outcomes. In this report, we propose a common set of metrics for measuring the effectiveness of two- and four-year institutions in enabling degree-seeking students who start college at a community college to transfer to four-year institutions and earn bachelor's degrees. These include three community college measures -- transfer-out rate, transfer-with-award rate, and transfer-out bachelor's completion rate -- and one measure for four-year institutions -- transfer-in bachelor's completion rate. We also examine a fifth measure: the overall rate at which the cohort of students who start at a community college in a given state go on to earn a bachelor's degree from a four-year institution. In the conclusion of the report, we discuss implications for institutional leaders and policymakers and identify areas for further research.