Not only is His Highness Sheikh Khalifa bin Zayed Al Nahyan the ruler of Abu Dhabi, he's the ruler of the whole United Arab Emirates. In addition to this all, he has the tallest building in the world, the Burj Khalifa, named after him. I guess that's what happens when you lend the people who built it the money to finish it.
He has been the ruler of the U.A.E. since his father, His Highness Sheikh Zayed bin Sultan Al Nhyan died in 2004. Sheikh Khalifa has been doing a wonderful job since then.