The company has targeted small to mid-sized businesses as its key market for its telecommunications services. Initially, the regional office will concentrate on the county's key business centers of White Plains, Mamaroneck, Mount Vernon, New Rochelle, Port Chester and Yonkers.

"Westchester County, with its rapid growth in small to mid-sized businesses, is an ideal market for our company," said Patrick Foley, general manager for ATG's Westchester and Fairfield County offices. "We see tremendous opportunities for growth in this county for our services."

The company, which offers local exchange, domestic and long distance phone service as well as high speed data and Internet services, took space on the fourth floor of the building which totals more than 380,000 sf of space. Reckson Associates Realty Corp owns the property.