Man has lived together with microbes for so long that we have become completely dependent on their presence. Most microbes reside in biofilms; structured communities encased in a protective matrix of biopolymers. Under healthy conditions, the microbial biofilm is in balance with itself (endo-balance) and with the host (exo-balance). Integrity of the skin is an important immunological function. Wounds go through a well-orchestrated series of healing steps. However, if for some reason healing times are extended, serious problems related to infection and homeostasis can develop. Based on recent advances in biofilm research and microbiological identification we discuss two hypotheses describing the role of microbial biofilms in chronic wound biology. The first hypothesis describes microbial biofilms as the cause of extended healing times. The second hypothesis is based on the host as cause of extended healing times and basically treats microbial biofilms as a logical consequence of failure to re-build the integrity of the skin.