Although a third of the public still believe that antibiotics work against coughs and colds, simply getting the public to believe otherwise may not be enough to reduce the level of prescribing. The large Department of Health sponsored household survey demonstrated that those with a greater knowledge about antibiotics were no less likely to be prescribed an antibiotic, and although those with increased knowledge about antibiotics were more likely to complete a course they were also more likely to self-medicate and to keep left-over antibiotics. Future campaigns that are aimed at reducing the level of prescribing should be focused towards those more likely to be prescribed antibiotics at present: younger women and those with a lower level of education. They should also examine and consider modifying consultation behaviour and other behavioural components involved in patient' expectations for antibiotics. This should include delayed antibiotic prescriptions. The easiest way to reduce the use of leftovers may be to shorten the course of antibiotics prescribed to 3 or 5 days. We should also promote a 'Do not recycle antibiotics' message towards the more highly educated, young women who are more likely to store, take and share antibiotics without advice.