Sweden’s Volvo (VOLVY) is doing something similar along with local startup Urb-it, but DHL is the biggest logistics company in the world.

The “Smart ready to drop” service went through field testing with 30 drivers last year, and in the fall it will progress to a beta test in Stuttgart, then Cologne, Bonn and Berlin. Daimler said the service will eventually roll out to seven cities in Germany.

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A spokesperson for Daimler told Fortune that, while the beta test is limited to Germany, the service may roll out abroad if the results show that customers use the service enough.

Smart drivers who sign up to the beta test will get a free “connectivity box” retrofitted to their vehicles, essentially to make their car a “connected car” (the box will come preinstalled in a special edition of the Smart Fortwo in the fall).

They will be able to generate a transaction number in a Smart smartphone app, for inclusion in the “c/o” field of the delivery address. The app then tells the delivery driver where to go. Similarly to Volvo and Urb-it’s system, the delivery driver will be able to use the transaction number to open the trunk of the recipient’s Smart car within a certain time window.

Once the package is in the car, the delivery driver locks the trunk automatically and the transaction number immediately expires.

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The service was developed in Daimler’s Smart Lab thinktank, which aims to come up with “creative urban mobility projects.”

As with other car manufacturers, Daimler is trying to diversify its traditional model as (depending on who you listen to) mass car ownership looks less certain in the future. With cars being parked most of the time, it certainly makes sense to find new ways to use them.

On Tuesday, Daimler also announced the merger of its MyTaxi ride-hailing service with a British rival, Hailo.