Mendeley has created an open source citation style editing tool, integrated into the latest version of Mendeley Desktop. The tool was created in collaboration with Columbia University Libraries, and with support provided by the Alfred P. Sloan Foundation. It is based on the open XML Citation Style Language (CSL).
Editing and creating citation styles was the most requested feature on the Mendeley Feedback Forum. Instead of creating a proprietary citation editing tool and style library, Mendeley chose to release the code for the tool as open source under the MIT license, which means other applications that work with citation data can also benefit from this work. Mendeley was able to not only make it easier for researchers to customize and create styles, but also to make it easier for them to collaborate with colleagues who may use a different tool that implements CSL.
[Lynne M. Fox, Education Librarian]