There are several options: metered parking, street parking in the neighborhood and there is a parking garage very close by (in the same row of shops). Some days they offer valet parking at the restaurant. If you metro, it is on the red line and it right by the Friendship Heights metro stop.
I usually park under the building. Maggiano's validates the parking stub so it isn't exhorbitant, and there's obvious protection from the weather. They've recently installed a more convenient automated payment system.
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