National September 11 Memorial & Museum at the World Trade Center Foundation

Websites outnumber phone numbers here, which is rare in this directory: 2,012 of the 2,073 offices listed in New York carry a website and 1,976 carry a phone number. That tells you what kind of entry this is. An office listing is a mailing address and a front desk, not a storefront you drop into.

The concentration is severe even by Manhattan standards. ZIP 10001 holds 176 offices, 10018 has 152, 10022 has 138 and 10017 has 135, four adjoining ZIPs on the same stretch of Midtown. If you are checking whether a company is really at the address it prints, start with the ZIP and work from there. Sponsored rows are paid placements, always labeled. A business can claim its entry and update the floor, phone, or website.