Site59.com was launched in May 2000 by travel and tourism professionals from The Boston Consulting Group (BCG) and was further developed and backed by iFormation Group, a partnership between BCG, Goldman Sachs and General Atlantic Partners.

Named for the 59th minute, Site59 specializes in making the best deals available at the last minute. Site59 assembles inventory in real time from thousands of industry suppliers, including major airlines, hotel companies, car rental companies and hundreds of specialty providers worldwide. In addition to its own web site, Site59 operates a private label distribution (ASP) product, powering last-minute sections of Travelocity, AOL Travel, CheapTickets, Yahoo! Travel, American Airlines Vacations, Delta Air Lines Vacations, Continental Airlines Vacations, Northwest's nwa.com, and Bestfares.com, among others.

In March 2002, Travelocity acquired Site59 for $43 million in cash. Site59’s CEO and founder, Michelle Peluso joined Travelocity with the acquisition as senior vice president, product strategy and distribution. Peluso became Travelocity’s COO in April 2003 and was then named president and chief executive officer of Travelocity in December 2003.

As of early 2005, many members of Peluso’s former management team at Site59 now hold senior management positions at Travelocity, namely Jeffrey Glueck (Chief Marketing Officer), Damon Tassone (Deputy CEO, lastminute.com), Tracey Weber (Chief Operating Officer, Travelocity North America), Richard Harris (Senior Vice President, Strategy and Business Development), Josh Feuerstein (Senior Vice President and Hotel Segment Manager), Josh Hartmann (Vice President, Software Development) and Jonathan Perkel (Vice President & Deputy General Counsel).

Site59 recently announced an impending shutdown, with all travel deals being moved to lastminute.com. Currently, deals are available on both sites, but Site59 will eventually cease to exist as a consumer brand.