Equity Residential is a real estate investment trust. The Company's primary business is the acquisition, development and management of multifamily residential properties. Its segments include Boston, New York, Washington D.C., Southern California, San Francisco, Seattle and Other Markets. Southern California includes Los Angeles, San Diego and Orange County. Other Markets includes Phoenix. It is engaged in leasing of apartment units to residents. It focuses on rental apartment properties in urban and high-density suburban coastal gateway markets. As of December 31, 2016, the Company owned 302 properties located in 10 states and the District of Columbia consisting of 77,458 apartment units. The Company's projects include The Alton, 455 Eye Street, 855 Brannan, Cascade, One Henry Adams, 340 Fremont and Vista 99. ERP Operating Limited Partnership (ERPOP) conducts the multifamily residential property business of Equity Residential.