As educators, government officials, and foundations leaders have embraced the agenda of dramatically increasing college success and credential completion, they have come to understand the need for better data on student outcomes to guide the improvement efforts of institutions, systems, and states. The data on degree completion and other final outcomes are too little, too late if the ultimate goal is improving rather than just reporting outcomes. What is needed are good comparative data on intermediate steps along the way to completion that are associated with earning degrees. Such measures are likely to include basic skills acquisition and the completion of a specific number of credits or particular gateway courses. In this paper, the authors assess the state of the emerging field of defining, measuring, reporting, and rewarding student progress in achieving "intermediate measures of success." This paper distinguishes between milestones that must be attained in order to get to completion and success indicators that increase a student's chances of completion. The authors review 11 cases of the use of intermediate measures by multistate, single-state or single-system, and multi-institution initiatives, noting differences in approaches, definitions, and uses of "milestones" data. This paper concludes with clear advice for the "next generation" of efforts to collect and report data on intermediate measures. The goal is to encourage common practices and definitions, as well as more thoughtful and effective uses of these data for institutional improvement, policy reform, performance funding, and accountability purposes. Appended are: (1) Summary of Milestones and Success Indicators; and (2) Detailed Descriptions of Milestones and Indicators. (Contains 2 tables, 2 figures and 7 endnotes.)