As the word exascale implies, the forthcoming generation exascale supercomputer systems will deliver 1018 flop/s of scalable computing capability. All that computing capability will be for naught if the storage hardware and I/O software stack cannot meet the storage needs of applications running at scale—leaving applications either to drown in data when attempting to write to storage or starve while waiting to read data from storage. Suren Byna, PI of the ExaIO project in the Exascale Computing Project (ECP) and computer staff scientist at Lawrence Berkeley National Laboratory, highlights the need for preparation to address the I/O needs of exascale supercomputers by noting that storage is typically the last subsystem available for testing on these systems.