How can I buy tickets for a single Citi Open Tournament session?

SeatGeek is now the Official Primary Ticketing Partner of the Citi Open Tournament! You can buy tickets online at SeatGeek.com, and depending on availability, at the Fitzgerald Tennis Stadium at Rock Creek Park Tennis Center box office during the tournament. You can follow the Single Sessions page for updates on daily ticket availability during the event.  Many sessions sell-out so the recommendation is to purchase in advance.