This text summarizes the conclusions of the French Working Party to Promote Research to Control Bacterial Resistance, initiated by the French Institute for Public Health Surveillance. The goal was to identify and prioritize the research areas most pertinent to the evolution of antibiotic resistance. The working group was part of a nationwide consultation of experts in the field of bacterial resistance and was coordinated with 2 other groups addressing (1) the use and surveillance of resistance to antibiotics and (2) the control and prevention of resistance to antibiotics. The proposals were discussed at a meeting held on 13 January 1999 by a large group of French microbiologists and clinicians who specialize in infectious diseases. The expert panel stressed that the determinants of evolution of antimicrobial resistance and the possibility of reversing this evolution are not completely known or understood. It emphasized the need for efforts to anticipate emergence of new resistances, to analyze the consequences of bacterial resistance, to develop rapid tests for determination of susceptibility to antibiotics, and to develop new antibiotics.