Duangrat's
Duangrat's, web site, 5878 Leesburg Pike, Falls Church, VA, near Bailey's Crossroads, 703-820-5775, usually open (Metro Trip Planner - opens in new window) [Washingtonian | WaPo | City Paper | food-plan | openlist | Yelp | Gayot]
Gourmet Thai at reasonable prices. The ruling Thai restaurant in this area. There is another branch of the same restaurant, with a slightly different menu, right next door, called Rabieng's. Has more modern decor than Duangrat's, but fewer offerings, although I am told you can still order off the Duangrat's menu. It used to be that every dish here was great, then for a while it turned spottier. Now it has been reinvigorated. It remains not fully consistent but the best dishes are better than ever and the menu is more innovative than ever before. The weekend “Thai tapas” are especially fun. Go, and go often.