BMW and Daimler have signed a memorandum of understanding to work together in the development of future autonomous driving systems. The agreement adds strength to BMW's existing collaboration approach, which also sees Fiat Chrysler as part of of the same scheme.

But this new agreement sees two of Germany's biggest car brands pulling in the same direction - up to SAE Level 4 autonomy. The announcement specifies highway driving, parking, and driver assistance systems, but it is noted that it might extend beyond level 4 to fully autonomous level 5 vehicles in the future.

When we spoke to BMW at the LA Motor Show in 2018 it was clear that BMW's view was that many of the current research programmes looking at future autonomous driving features would fail and that the company saw collaboration as key to success.

• How BMW is developing its autonomous driving system

The focus here is very much on safety, with Ola Källenius, member of the Daimler board and responsible for research at Mercedes-Benz saying: "Instead of individual, stand-alone solutions, we want to develop a reliable overall system that offers noticeable added-value for customers. Working with the right partners, we want to make significant advances in enhancing the performance of this technology and bring it safely on the road."

BMW has been fairly bullish about its plans to put a level 3 autonomous car on the road in 2021 - embodied in the BMW Vision iNext - while Daimler says it's uniquely placed to apply autonomy across a wide range of segments, from passenger vehicles to vans and trucks, "early next decade".

Ultimately, the agreement sees two big companies working on autonomous driving solutions and that may see them gaining critical mass in developing a solution that gains wider adoption within the industry.

You can find out all about the SAE-defined autonomous driving levels in our dedicated feature.