This is an exploration of the efforts to promote open access (OA) to publicly funded scholarly research, specifically those projects supported by the National Institutes of Health (NIH), the largest supporter of medical research in the world.  It analyzes the research support for highly cited articles in several science, technology and medical (STM) journals.  In addition, the current impact of the NIH’s mandatory open, public access policy, which requires freely accessible online publication in the National Library of Medicine’s PubMed Central within 1 year after initial publication, is reviewed. Finally, this paper discusses the evolution of the NIH policy, opposition to its mandate, and other issues of open access and scholarly publishing.