This series of presentations was given at the EarthCube Data Facilities End-User Workshop held January 15-17, 2014 in Washington, DC. This workshop provided a forum to discuss the unique requirements and challenges associated with developing the communication, collaboration, interoperability, and governance structures that will be required to build EarthCube in conjunction with existing and emerging NSF/GEO facilities. This panel and discussion, specifically, outlined and explained several current concepts in data sharing and interoperability, featuring presentations by: Paul Morin (UMN): Polar Cyberinfrastructure Don Middleton (UCAR): Atmospheric/Climate Kerstin Lehnert (LDEO): Domain Repositories & Physical Samples David Schindel (CBOL, GRBio): Biological Perspective & Collections Hank Leoscher (NEON): Observation Networks Daniel Fuka (Virginia Tech) and Ruth Duerr (NSIDC): Brokering Ilya Zaslavsky (UCSD): Cross-Domain Interoperability