Historically, community colleges have promoted social mobility by providing access to higher education, especially for underrepresented groups. Because of their geographic availability, open admissions policy, and low cost, these colleges have expanded educational opportunity to millions of Americans, young and old. Recently, however, the emphasis has shifted from access to completion, an area where community colleges have underperformed, at least as conventionally measured. Yet completion is not an end in itself, as the ultimate goal is to provide, along with the rest of higher education, an avenue for upward mobility for those that enroll. This article uses an important new dataset that attempts to measure the contribution of community college to social mobility. Leaders should be aware of this new measure because it says something important about outcomes and because it may very well become a new metric for judging the effectiveness of community colleges.