This paper is concerned with how those who prescribe antimicrobials should consider the wider repercussions of their actions. It is accepted that in an ecological system, pressure will cause evolution; this is also the case with antimicrobials, the result being the development of resistance and the therapeutic failure of drugs. To an extent, this can be ameliorated through advances by the pharmaceutical industry, but that should not stop us from critically appraising our use and modifying our behavior to slow this process down. Up to 50% of prescribing in human medicine and 80% in veterinary medicine and farming has been considered questionable. The Alliance for the Prudent Use of Antimicrobials (APUA) was approached by the WHO to review the situation. Their recommendations include decreasing the prescribing of antibacterials for nonbacterial infections. In the UK, there has been an initiative called "the path of least resistance". This encourages general practitioners to avoid prescribing or reduce the duration of prescriptions for conditions such as upper respiratory tract infections and uncomplicated urinary tract infections; this approach has been successful. Another recommendation is to reduce the prescribing of broad-spectrum antibacterials. In UK hospitals, the problems identified with the inappropriate use of antibacterials are insufficient training in infectious disease, difficulty in selecting empirical antibacterial therapy, poor use of available microbiological information, the fear of litigation and the fact that the majority of antibacterials are prescribed by the least experienced doctors. With close liaison between the laboratories and clinicians, and the development of local protocols, this can be addressed. Another recommendation is to tighten the use of antibacterial prophylaxis and to improve patient compliance. Through a combination of improved education for doctors and patients, and improved communication skills, these problems can be addressed. A further recommendation is to encourage teaching methods that modify prescribing habits. It has been shown that workshops have led to a significant reduction in the prescribing of broad-spectrum antibacterials in the community. Auditing the prescribing of antibacterials has also been recommended. Surveillance systems around the world monitor trends in resistance: the European Antimicrobial Resistance Surveillance Progamme (EARSS) monitors antibacterial resistance; the WHO and the International Union Against Tuberculosis and Lung Disease collaborate to monitor tuberculosis; the WHO and the International AIDS Society monitor HIV. In the third world, a bigger problem than resistance is whether drugs are even effective, as they are often spoiled by climactic conditions, and poor quality generics and counterfeit drugs are common. Also, patients may not be able to complete a course for financial reasons. Facts about Antimicrobial Resistance in Animals (and Agriculture) and Impact on Resistance (FAAIR) was commissioned by APUA. They conclude that the nonhuman use of antibacterials can lead to the development of antibacterial resistance in human pathogens. The European commission banned the use of antibacterials as growth promoters in 1999. In the Western world, we should improve our diagnosis of sepsis, access local guidelines and consider withholding treatment pending investigations, decide if treatment can be stopped earlier and treat the patient not the result. Many developing countries need improved access to more antimicrobials, preferably in the controlled environment of appropriate medical advice.