The worldwide increase in resistance to antimicrobial drugs has made reducing the unnecessary use of antibiotics a public health priority. There have been campaigns in many countries to educate the public about appropriate use of antibiotics in outpatients. By use of a comprehensive search strategy and structured interviews, we were able to identify and review the characteristics and outcomes of 22 campaigns done at a national or regional level in high-income countries between 1990 and 2007. The intensity of the campaigns varied widely, from simple internet to expensive mass-media campaigns. All but one campaign targeted the public and physicians simultaneously. Most campaigns that were formally evaluated seemed to reduce antibiotic use. The effect on resistance to antimicrobial drugs cannot be assessed accurately at present. Although the most effective interventions and potential adverse outcomes remain unclear, public campaigns can probably contribute to more careful use of antibiotics in outpatients, at least in high-prescribing countries.