The search for new drugs takes on greater complexity with increasing knowledge, allowing more sophisticated therapeutic interventions. At the same time there is increasing commercial pressure for the pharmaceutical industry to find 'blockbuster' drugs which will be marketed globally to maximise profit in the shortest possible time. Other changes in the industry--shortened times for drug development and increasing outsourcing of functions--make for an environment where some pre-marketing safety issues may go unnoticed. The increasing challenge to pharmacovigilance is not only to be able to find early signals of drug problems, but to rapidly determine the true benefits and risks. We may not have adequate systems to prevent unnecessary harm from globally marketed drugs.