The PSI develops and ratifies standards as part of the community and as such attempts to foster synergistic activities with other organizations within the community in order to maximize its impact. As one of the long-standing HUPO initiatives, the PSI undertakes development efforts that further the mission of HUPO, its other initiatives, and major projects such as the Human Proteome Project (HPP). An important example is the participation in the development of the HPP MS Data Interpretation Guidelines (versions 1, 2.1, and 3.0) as described above. These guidelines are not formally a PSI product, but were developed with the extensive experience of PSI members. As also highlighted above, the PSI cooperates extensively with the ProteomeXchange and the IMEx Consortia, which both actively use and promote the PSI standards.