This document proposes establishing a documentation network to facilitate open sharing of documentation data among cultural heritage institutions. The network would have open membership and annual reporting overseen by group representatives. It would establish guidelines for interoperability across documentation systems and standards. The goal is to make more documentation data accessible by sharing it in graphs, tables and online, rather than being restricted to documents, to allow for new insights and re-use of data for other purposes. This would create extra value from data collected during documentation projects.