There are thousands of medical journals worldwide, many of them publishing articles that report diabetes-relevant research. The growth of Internet publishing has made this knowledge universally available – in theory. However, the contents of peer-reviewed medical journals are beyond the reach of most of the world’s healthcare providers and indeed most people with diabetes. Publishers limit access to the latest research findings to those institutions and individuals that can afford to pay for it. Paul Chinnock puts forward the case for open access publishing, and describes the principles and achievements of the open access movement, focusing on one of the key players – the Public Library of Science.