For as long as we here at N&S can remember, the US Embassy in London--with whom the United States has a "special relationship," it is said--has been at Grovesnor Square in downtown Mayfair.

But the 1960s-era building is getting old and crowded, and the U.S. State Department is moving to new turf, both physically and stylistically.

This artists' rendering is a conception of what the new US Embassy in London will look like when it opens around 2017.

The State Department announced on Tuesday that the Philadelphia firm KieranTimberlake has won a hard-fought design competition for the new Embassy, which is expected to cost about $500 million.

For those of us who have spent a fair bit of time in US embassies overseas, one thing stands out: this one is a big departure from the forbidding, fortress-like structures that one can see in many a foreign capital, such as Baghdad; Amman, Jordan; and Riyadh, Saudi Arabia. Those designs, the product of embassy attacks in the 1980s, were often a major turn-off, U.S. image-wise, in the host country.

This one departs from the "Standard Embassy Design," incorporating such security feartures as the partial moat (very British!) and setbacks from the road. It will be built on the south bank of the Thames River. Oh, and it's supposed to be energy efficient, too.