Leasing has begun for the six-story, 440,000-square-foot Tyson Courthouse building at the intersection of Old Courthouse Road and Chain Bridge Road at Tysons Corner. Architect Volker Zinser designed the building to have a 120-foot arch on the plaza.

The George Hyman Construction Co. has begun work on the 1.4-million-square-foot National Place at 14th and E streets NW. The $140 million project of Quadrangle Development will include a J.W. Marriott Hotel, a shopping plaza to be operated by the Rouse Co. of Columbia and 410,000 square feet of office space. The historic National Theater will be preserved on the site.

Nathan Isikoff of Carey Winston Relators has leased 40,000 square feet in a new building on Wilkins Avenue in Rockville to the Department of Health and Human Services. Richmarr Construction is the builder.

Group Health Association of America has leased 10,830 square feet in the new YWCA building at 624 9th St. NW.

Kan Am Realty Inc., a realty investment firm based in Atlanta, has purchased a majority interest in the suburban shopping center called Germantown Commons in upper Montgomery County, with Western Development Corp. as a partner. Completion of the shopping facility is scheduled next spring.