Maddox, Hoppe, Hoofnagle & Hafey, LLC, provides legal representation to clients in the Tri State Area of Maryland, Virginia, and Washington DC, including Bethesda, Columbia, Chevy Chase, Rockville, Silver Spring, Gaithersburg, Annapolis, Upper Marlboro, Bowie, Laurel, College Park, Forestville, Hyattsville, Arlington, Alexandria, Fairfax, Reston, McClain, Tyson's Corner, Herndon, Manassas, Leesburg, Wheaton, Sandy Springs, Landover, Annandale, and near the Pentagon.

In addition, the firm serves clients in the counties of Montgomery, Prince George's, Arlington, Fairfax, Loudoun, Anne Arundel, and Howard.