Arriving freshly into the country and looking to hire a car was actually pretty easy. I entered on a 30 day tourist visa and was allowed to hire a vehicle and drive away quite happily on my UK licence.
My wife, on the other hand, had the beginnings of a work permit and residence visa, so her UK licence wasn't good enough, and she needed to wait until first her National ID card came through, before getting herself a local licence before she was allowed to drive our hire car. so I played taxi for a month, which was absolutely fine.
Then, however, I started the process of getting myself UAE Residency, which then made my UK licence invalid, so I wasn't legally allowed to drive our hire car. Great. But how do you go about getting your UAE licence?