Morocco has a very bad road safety record. Accidents are common and fatalities are too.
There's a good network of motorways (expressways) between major cities, but expect to see some driving which is best described as "free form". Even if others aren't, stick to the speed limit and drive defensively (ie expect the unexpected and the downright insane).
Driving in the cities is chaotic. Might equals right, and trucks buses, cars horse-drawn carts and pushed trolleys all compete for the available road space. Horn honking is constant and despite the level of noise, almost totally pointless.
It'll take nerves of steel to drive in places like Marrakesh. It's not that large anyway, so the cheap taxis and buses are a better option.
If you intend to drive through the Atlas mountains expect to encounter very poor road conditions. A four wheel drive is recommended.
All the major car rental companies operate in Morocco. There a re a few local outfits too, but make sure to check the condition of the car carefully.
Petrol is on par with European prices, but stick with the brand name service stations.... local outlets often deliver poor quality fuel.
Avoid driving at night if at all possible, the darkness makes the camels, donkeys and pedestrians walking in the middle of the road harder to see.
And have a look at our other safety tips for Morocco.
Phil from the safety hub about 7 years ago