"Reuter said Zipline is communicating with blood banks, health systems and clinics and learning how to most effectively communicate with clients. "It's difficult to do that at scale," he said. "The hard part of drone delivery is not making a drone that can carry something. It's building a service that can run every day, making thousands of deliveries in a reliable manner, and do so in an economically sustainable way," said Reuter, who has been to Zipline's first distribution center in Rwanda. "We believe Rwanda can serve as a model for the rest of the world in how to enable drone delivery.""