From the start, the JDP has been based on the enormous generosity of participating publishers and independent journals, most of which have supported the Project's libraries with donations for over a decade and with deep discounts for nearly half as long. The journals they provide, both as donated and deeply discounted subscriptions, along with their willingness to assume the significant postage cost of mailing subscriptions to libraries, are the lifeblood by which the JDP is sustained.
Without their continued commitment, the JDP would have been little more than a good idea. Their donations and discounts not only have made the support of libraries possible but also have helped leverage foundation support for the JDP and directly for libraries. Through their participation with the JDP, the over 500 publishers who have worked with JDP over the years have played a central role in the revitalization of libraries and scholarship. Many publishers donate 10 to 20 subscriptions per year while offering additional subscriptions at discounts of over 50 percent. Approximately 85% of journals offer free access to electronic versions with a current print subscription.