Amazon is launching a service that will let couriers open people's front doors and put deliveries inside.
Users of Amazon Key will need a smart lock and Cloud Cam camera.
Couriers will scan a package barcode and once the delivery has been verified online, the camera will start recording and the delivery person will be able to unlock the door using an app.
One analyst said consumers would have to be convinced the system was secure if they were to use it.
Users will be able to choose to watch the delivery live or receive a short video after the drop-off.
Compatible smart locks include models made by Yale and Kwikset.
The system can also be used to give access to dog walkers, cleaners or visiting guests.
The online shopping giant has long sought ways of improving delivery convenience for customers - including a trial with Audi in 2015 in which packages were deposited in car boots.
