There are currently strong drivers from funding bodies for the scientific community to both preserve data and make it available more widely, whilst ensuring that privacy and confidentiality are maintained. Institutional data sharing policies will be required to encapsulate the response of individual institutions to these pressures. When organisations share data they adopt these policies into data sharing agreements between institutions which must then be enforced. The approach to enforcing scientific data sharing agreements presented here is based upon a combination of trust, leading-edge technology, licensing and legal frameworks. The scientific community must decide what balance between these components it wants to adopt.