Recent developments in OER and MOOCs (Open Educational Resources and Massive Open Online Courses) have raised questions as to how learners engaging with these courses and components might be assessed or credentialed. This descriptive and exploratory paper examines PLAR (Prior Learning Assessment and Recognition) as a possible answer to these questions. It highlights three possible connections between PLAR and open education which hold the greatest promise for credentialing open learning experiences: 1) PLAR may be used to assess and credential open educational activities through the use of exam banks such as CLEP (College Level Examination Program); 2) Learning occurring in xMOOCs (MOOCs based on already credentialed courses) and in other open contexts resembling "courses" may be assessed in PLAR through course-based portfolios; and 3) PLAR may also be enabled through the specification of "gap learning" facilitated through OER of many different kinds. After describing these options, the paper concludes that although the connections leading from open educational contexts to PLAR credentialing are currently disparate and "ad hoc," they may become more widespread and also more readily recognized in the PLAR and OER communities.