The human skin is a dynamic ecosystem inhabited by bacteria, mites, fungi and viruses. This set of microorganisms living on the skin and mucous membranes of the oropharynx, upper respiratory tract, conjunctiva, colon and lower urogenital tract, is called „normal flora“ (physiological, natural, autochronous, microbiome, microbiota) and is essential for skin physiology and immunity. The development of molecular methods to identify microorganisms has led to an emerging view of the resident skin bacteria as highly diverse and variable. An enhanced understanding of the skin microbiome is necessary to gain insight into microbial involvement in human skin disorders and to enable novel promicrobial and antimicrobial therapeutic approaches for their treatment.