 What does removing price barriers mean for readers?
Suppose that selling their work would actually harm their interests by shrinking their audience, reducing their impact, and distorting their professional goals by steering them toward popular topics and away from the specialized questions on which they are experts. A price tag is a significant access barrier. OA removes price barriers. As a result, users may be hampered in their research by barriers erected to serve intermediaries rather than authors. Removing price barriers means that readers are not limited by their own ability to pay, or by the budgets of the institutions where they may have library privileges. Removing permission barriers means that scholars are free to use or reuse literature for scholarly purposes. These purposes include reading and searching, but also redistributing, translating, text mining, migrating to new media, long-term archiving, and innumerable new forms of research, analysis, and processing we haven’t yet imagined. While every kind of OA removes price barriers, there are many different permission barriers we could remove if we wanted to. If we remove price barriers alone, we provide gratis OA , and if we remove at least some permission barriers as well, we provide libre OA . If there are complexities, they lie in the transition from where we are now to a world in which OA is the default for new research. This is complicated because the major obstacles are not technical, legal, or economic, but cultural.
 Readers are not limited by their own ability to pay.
 Readers are not limited by the budgets of libraries.  Readers can translate and redistribute work.  Readers can reuse literature for scholarly purposes.  Readers are not limited by their own ability to pay.