Free and open to the public. No tickets required, but Dumbarton House likes to take reservations so they know how many chairs will be needed. Please go to http://dumbartonhouse.org/events to register, particularly if you have a group. Walk-ins welcome as well.
Dumbarton House is fully ADA accessible. Handicapped parking is available in the parking lot located off 27th Street, just north of Q Street.
The closest station is the Dupont Circle Station via the Red Line. From the Q Street exit, the house is approximately six blocks west on Q Street, NW, just over the Q Street Bridge leading to Georgetown, a short walk or ride on the D2 or D6 bus lines.