Actually it's more of a long-term engagement between them as Daimler has a lousy track record when it comes to more permanent relationships – oh, and we mustn't forget the third party in this relationship, .
So, what's in it for everyone and what's not?
For a start what you won't see is any badge swapping, but will get Merc powertrains and M-B's Vito commercial vehicles will get small capacity diesels and transmissions from Renault.
This is more about sharing sub-systems; the next generation smart will benefit Twingo underpinnings enabling it to expand the product portfolio of a marque that is failing to hit the high sales notes and profitability, the latter due to the smart's unique structure and powertrain.
And with vehicle electrification the industry buzz phrase all three will be able to share the costs of electric motors and drive down the price of batteries, that might eventually make EVs sensibly priced.
Daimler and Renault-Nissan may have taken a 3.1% equity stake in each other and future plans might include sharing manufacturing facilities, but that's about as far as it will go.
Even so the thought of Teutonic, Gallic and Japanese engineers working on a joint project has Simpsons-like levels of comedy potential.
For a start will it be Bratwurst and beer, Coq au Vin and Burgundy or Sushi and Saki on the menu?