The ADA recommends the following

The American Dental Association (ADA) is aware of the recent preliminary injunction against a mouthwash manufacturer's advertising claim that its mouth rinse is as effective as flossing. The ADA continues to recommend flossing as part of a good oral hygiene regimen. The following flossing information was updated and posted on the ADA's Web site in June 2004.
While some study results* indicate the use of a mouth rinse can be as effective as flossing for reducing plaque between the teeth, the American Dental Association (ADA) recommends to brush twice a day and clean between the teeth with floss or interdental cleaners once each day to remove plaque from all tooth surfaces. Plaque is responsible for both tooth decay and gum disease.
for more information visit the ADA website.