Providing college credit for prior learning is nothing new. The American Council on Education's Credit Recommendation Service (CREDIT), the largest national program making credit recommendations for workplace and other training, dates to 1974. Several colleges that specialize in the practice--Excelsior and Empire State in New York, Thomas Edison in New Jersey, Charter Oak in Connecticut--were similarly founded in the early 1970s. But granting credit for prior learning through Prior Learning Assessment (PLA) has never really caught on. This article discusses PLA, which offers a proven pathway to raise productivity in higher education, to enable millions of students who have stopped short of a degree to complete their education, and to increase the application of more authentic and student-centered forms of assessment. PLA also offers a ready way to incorporate the past decade's revolution in open courseware and open learning into the existing framework of accreditation and assessment, making a college degree more affordable and accessible to all. To understand the importance of portable credits, one must stipulate two truths: (1) most students don't start and finish at the same college; and (2) lots of important learning takes place outside school. People are at the very beginning of seeing what free and open courseware can do to transform higher education. PLA offers a clearly marked way forward. (Contains 6 resources and 9 online resources.)