Enthusiasm after discovery of antibiotics and their use in clinical practice led to presumption that problems of bacterial infections will be soon resolved and forgotten and attention will be turned to other serious problems, such as viral infections or neoplastic diseases. However, instead of disappearance of bacterial infections, bacterial pathogens become more resistant to many antibiotics. The ability of bacterial strains to acquire resistance genes from other bacteria, even of different species, causes increasing stability of resistance of bacteria. Transferable elements - resistance genes - often interact and create changed structures; this enables to preserve, stabilize, or under special conditions, transfer resistance genes. Transferable elements include plasmids, transposons, integrons and gene cassettes. Conjugation of bacteria, transduction by bacteriophages and transformation are the mechanisms by which these elements are transferred. A very significant property of transferable, mobilisable and transposable genetic systems of resistance is their stability and ability to adapt to new hosts. They do not lose it in the absence of antibiotics. The generally pessimistic view on future antibacterial chemotherapy should be a challenge to prevent the existence and spread of resistant strains of bacteria. It is much simpler and more convenient than „quench the fire“ later. Best scheme is to stop resistance before it starts.

        Key words: reservoirs, interaction, antibiotic resistance, transfer resistance genes.