Authors James A. Green, Health Research Institute, University of Limerick, Ireland Gjalt-Jorn Peters, Open Universiteit, the Netherlands Sara Schiavone, Ilse Pit, Institute of Human Sciences, University of Oxford, UK Elena Sixtus, Universität Potsdam, Germany Cillian McHugh, University of Limerick, Ireland Conor Smithson, Vanderbilt University, United States Background: Unpublished studies, the so-called file-drawer, present a threat to the balance of published literature. This is especially the case where unpublished studies have null results, which will exaggerate the size of effects in the published literature. However, previous attempts to “empty the file-drawer” have required substantial effort, similar to writing a study up for conventional publication. Where a researcher has a substantial body of unpublished work, this is therefore very time-consuming, and it can be difficult to determine which unpublished studies are of the most interest. Methods: The OpenDrawer project was developed to provide a quick declaration that a study was conducted with a very brief outline. This was designed to be standardized and searchable, and would mean that unpublished studies could be identified, and the original authors contacted. Findings: OpenDrawer is a natively open platform for documenting unpublished studies, with a study being able to be briefly documented in less than five minutes. Discussion: Estimates of the volume of unpublished studies in other disciplines within and outside psychology are often high; currently there are no estimates for health psychology as a discipline. OpenDrawer provides an easy way for researchers to document work they have completed but not published, and will help other researchers identify relevant unpublished literature.