The ability of microorganisms to form multicellular three-dimensional associates (biofilms) increases significantly their resistance to the influence of negative environmental factors. One of the manifestations of this ability is the development of drug resistance, which leads to a decrease in the effectiveness of drugs and significantly complicates the treatment of the corresponding diseases. Despite the unabated interest in this extremely undesirable phenomenon, there is no generally accepted explanation of the mechanisms of resistance development. At the same time, the generalization of data on the properties of biofilms allows us to get closer to the understanding of this process, but also to substantiate the proposition about its negative impact on adjacent tissues.