It sounds like something out of science fiction - a floating fortress in the sky - but that's how internet retailer Amazon could be delivering your packages.
The company has filed a patent for an "airborne fulfilment centre" from which drones, also known as unmanned aerial vehicles (UAVs), will deliver items to their recipients.
The design resembles a blimp with a warehouse attached to it, which could hover around 45,000 feet in the air.
"As the UAVs descend, they can navigate horizontally toward a user specified delivery location using little to no power, other than to stabilize the UAV and/or guide the direction of descent," the patent application reads.
The system could also use "shuttles" to re-stock the warehouse with products, fuel and UAVs, as well as moving staff between the warehouse and the ground.
The patent also suggests drones could be used to delivery perishable items or prepared meals in a "timely fashion" to customers.
The company has already been testing drone deliveries under the name Amazon Prime Air, with its first successful product drop of a TV streaming stick and a bag of popcorn to a customer's garden earlier this month.
But it isn't the only major company dipping their toes into the drone delivery market. Pizza chain Domino's has also started deliveries via air, while convenience store chain 7-Eleven has already made more than 70 commercial deliveries - both are using the same company Flirtey.
Domino's New Zealand carried out its first-ever trial delivery in August and is also working on a land-based delivery robot.