Medical journal publishing has changed dramatically over the past decade. The shift from print to electronic distribution altered the industry's economic model. This was followed by open access mandates from funding organizations and the subsequent imposition of article processing charges on authors. The medical publishing industry is large and while there is variation across journals, it is overall highly profitable. As journals have moved to digital dissemination, advertising revenues decreased and publishers shifted some of the losses onto authors by way of article processing charges. The number of open access journals has increased substantially in recent years. The open access model presents an equity paradox; while it liberates scientific knowledge for the consumer, it presents barriers to those who produce research. This emerging "pay-to-publish" system offers advantages to authors who work in countries and at institutes with more resources. Finally, the medical publishing industry represents an unusual business model; the people who provide both the content and the external peer review receive no payment from the publisher, who generates revenue from the content. The very unusual economic model of this industry makes it vulnerable to disruptive change. The economic model of medical publishing is rapidly evolving and this will lead to disruption of the industry. These changes will accelerate dissemination of science and may lead to a shift away from lower-impact journals towards pre-print servers.