In January 1996, record snowfall halted urban functions for 3 or 4 consecutive days in the Sapporo, Japan, area. The Civil Engineering Research Institute concluded that lack of cooperation among the road organizations and improper provision of information to citizens aggravated the disruptions. Experiments on appropriate methods of sharing information and providing information to road users were conducted and collectively named the Greater Sapporo WHITE-NET Experimental Project. Under the project, the road information-sharing experiment has been performed since the winter of 1997-1998. Information on road maintenance and road conditions during snowstorms is shared by using an e-mail mailing-list system. In a questionnaire survey, more than 60% of respondents indicated that sharing information by e-mail was more effective than sharing by fax or website. The car commuter monitoring experiment was carried out to understand how car commuters change their commuting methods according to road and weather information. During the 1999-2000 winter, 31 monitors who own mobile phones that can access the Internet participated. Weather and road information was provided at 6:00 p.m. and 7:00 a.m. As a result, on February 25, when 45 cm of snow fell from night until morning, more than 10% of the monitors changed their transportation mode to public transportation.