Evolution of bacterial resistance to antibiotics could be better controlled if we knew how to define the potential of evolution of bacterial resistance towards a given antibiotic, prospectively. No unique method allows to do it. Pieces of answers can be obtained by using diverse methods using bacteriological, ecological pharmaco-epidemiological techniques and experimental models. Association of the results obtained with these various techniques is mandatory to understand the evolution potential of resistance towards a given antibiotic when it is used in the clinical setting.