Digital Realty is a company involved in datacenter acquisition, ownership, development and operation as well as providing colocation services. Digital Realty's customers include domestic and international companies across multiple industry verticals ranging from information technology and Internet enterprises, to manufacturing and financial services. Digital Realty's 228 properties, excluding three properties held as investments in unconsolidated joint ventures, comprise approximately 18.3 million square feet as of December 31, 2011 including 2.4 million square feet of space held for redevelopment. Digital Realty does its business in 31 markets throughout Europe, North America, Singapore and Australia.