A method of sharing data in a subsea network includes a plurality of nodes interconnected by a plurality of data connections arranged to carry data to and from equipment in subsea installations, the method includes: storing data in a mass subsea data store provided across one or more nodes in the subsea network configured to act as a subsea data server; and on receiving, at the subsea data server, a request for access to data stored in the mass subsea data store, the subsea data server retrieving the requested data from the data store and causing the requested data to be sent over the subsea.