The skin microbiota is part of the skin protective barrier to the external environment. The presentation will provide some insight into the skin microbiota and its analysis during cosmetic efficacy testing. Abstract: In the last years, the skin microbiota is increasingly popular in the cosmetic industry. But not only the cosmetic industry is interested in skin microbiota. Thanks to the gateway role played of intestinal microbiota related products, also consumers are becoming increasingly interested in products maintaining/preserving the skin microbiota equilibrium. Nowadays, DNA sequencing techniques allows to easily identify the bacterial strains living on the skin and an increasing number of scientific studies have shown that the skin microbiota is part of the physiological mechanisms of the skin playing an essential role in protecting the skin from the external environment. This advance in techniques and science, offers the cosmetic industry new insight in the efficacy testing field. The skin microbiota is, in fact, an opportunity to differentiate product and to introduce innovation in products development. But when it comes to skin microbiota, its molecular analysis (skin microbiome) and cosmetic products it is not exactly a marriage made in heaven. This is the reason why Complife R&D department has focused its effort in helping the cosmetic industry in finding the key to the problem.