After years of permanent decline the downtown of New York City has undergone a tremendous revival. Based on the Lower Manhattan Revitalization Plan implemented in 1995 the office vacancy rate has decreased from 23.1% to 7.5% in 1999. Many high-tech and internet companies relocated in Plug'n' Go and IT-Cluster buildings. Especially class B and C office buildings have been converted into apartment buildings. The new residents of Downtown Manhattan are predominantly young people. Since 1995, more than 5 000 residential units have been converted, an estimated 7500 units will be converted by 2002 when the downtown population is estimated to reach 30 000. This makes the downtown the fastest growing community in New York City. Together with 7.2 million tourists visiting Lower Manhattan each year the old central business district is developing to a 24-hour community.