This grant continues support for the development of Dat, a software platform for the versioning and management of tabular datasets. Inspired by Git, the popular system for version control among distributed software developers, Dat supports the tracking of dataset versions not just at the file level, but at the individual cell level, cataloging cell-by-cell changes to the data. A 2014 grant from the Sloan Foundation has enabled lead developer Max Ogden to move the system from a sketch to a substantial prototype, to ensure that the platform was developed with scientific data in mind, and to launch pilot applications in the sciences using genomic and astronomical data. Funds from this grant will allow Ogden, partnering with Waldo Jaquith of the U.S. Open Data Institute, to move from the current working prototype to a full version 1.0 release. Additional funds support outreach and partnership-building with labs and academic research institutions.