Watch an Amazon delivery driver walk into a customer's home and leave a package

CNBC First Look: Amazon Key

Amazon's new in-home delivery service, Amazon Key, is now available to Amazon Prime members in 37 cities and surrounding areas across the U.S., and we got a first look.

To get in-home delivery, customers need an Amazon Cloud Cam and a smart lock. When the driver arrives, they verify the location by scanning the bar code on the package. Then the camera turns on and unlocks the door. Customers can watch the footage of the in-home delivery via an app on their smartphone. No codes or keys are provided to the delivery drivers.

Customers can also use the smart lock to give family and friends special codes to open the door. Amazon is soon rolling out integrations with Merry Maids and pet sitters and dog walkers on and others via Amazon Home Services.

The stakes are high for Amazon — bad experiences could damage Amazon's reputation and open the company up to legal and liability issues. But if it works, Amazon reduces yet another customer pain point — the need to wait around for an important delivery.