The Achieving the Dream (ATD) initiative works with more than 100 community colleges across the United States with the specific goal of increasing student success. Together, Achieving the Dream colleges graduate or transfer close to 250,000 students a year. With just a 5 percent increase in graduation rates, individuals can positively impact the lives of an additional 12,500 students each year--or 62,500 students over five years. That's 62,500 "additional" students achieving a life-changing goal because of the work to which they are committing themselves today. Facilitating institutional change is not easy. It requires new organizational language, practices, interactions, and relationships--things that do not happen overnight. This guide is designed to achieve two objectives: (a) offer new language to clarify the use and purpose of various types of data, and (b) demonstrate how colleges can engage in the practice of identifying (or diagnosing) the underlying factors impeding student success and address such factors in the design of specific interventions or policy changes. Survey Instrument for follow-up study on "instructor issues" is appended. A list of resources is included. (Contains 7 tables.)