Segre and colleagues report a two-year longitudinal survey of the bacteria, fungi and viruses that make up the human skin microbiome, using samples taken at three time points from 17 body sites of 12 healthy individuals. Metagenomic sequencing revealed a remarkable stability of the microbial community at each site for each individual over time, which contrasts with the variability seen between sites and individuals. Dry sites, such as palms, and sweat glands tended to have more stable communities than moist sites, such as feet. Stability also varied between individuals, with 4 of the 12 individuals exhibiting greater instability across all sites than the remainder of the cohort. Single-nucleotide variations were used to track individual strains of Propionibacterium acnes and Staphylococcus epidermidis, which suggested that stability arises from the maintenance of strains after colonization rather than repeated colonization by specific favoured species.