Beijing and Vancouver, host cities of the next Olympic Summer and Winter Games, and the United Nations Environment Program (UNEP) jointly called on car owners in the two cities to drive one day less in 2007 to mark the World Environment Day.
The Construction and Environment Department of the Beijing Organizing Committee for the Games of the XXIX Olympiad (BOCOG) urged BOCOG staff to do their part in creating conditions for one more "blue sky" in the Chinese capital. In response to the call, 283 staff members said they would keep their cars at home and choose to take the bus or ride a bike on World Environment Day. Another 78 said they would take BOCOG's shuttle bus to go to work. The rest of the staff promised to drive one day less in the rest of the year
On June 5, 2006, BOCOG and the Beijing Municipal Environmental Protection Bureau staged a similar campaign. Tens of drivers' societies and clubs, as well as non-governmental environmental organizations, campus environmentalists and news media, called on fellow drivers to drive one day less. The campaign's follow-up on October 26, 2006 contributed largely to the smooth traffic and better air conditions during the Sino-African Summit in Beijing.