The important cooperative roles that pharmacists and manufacturers can play in submitting and evaluating adverse drug experience (ADE) reports are described. Hoffmann-La Roche receives approximately 100,000 drug-related reports and inquiries annually. These reports must be evaluated, and ADEs must be distinguished from anecdotal reports, queries, lack-of-effectiveness reports, or product complaints. An ADE report should include information about (1) the patient, including history and demographics; (2) the drug, including dosage and concomitant medications; and (3) the onset, resolution, and outcome of the event, which may be a reaction, an abnormal laboratory value, or a finding that the drug did not work as expected. Complete and accurate reports are more valuable, but reports of all potential ADEs should be submitted. The evaluation process that occurs at Hoffmann-La Roche when an ADE report is received is described. Possible outcomes include reports submitted to FDA, site visits (if clusters of reactions are reported), and introduction of new product labeling with stronger warnings. Pharmacists and other healthcare professionals should report ADEs to manufactures as well as to FDA.