Microbial adhesion to surfaces is the onset of the development of a biofilm. Biofilm formation occurs on all surfaces exposed to an aqueous environment, such as soft tissues, implanted biomaterials or tooth surfaces in the human body, rocks in rivers, pipelines in water works, and on ship hulls. Generally, microbial adhesion is preceded by the formation of a conditioning film of macromolecular components, after which mass transport processes ensure initial adhesion of microorganisms. However, clinically, microbial adhesion to surgical instruments, light switches in the operating theatre and cotton fabrics in the absence of a conditioning film may also add to the transmission of pathogens in a hospital environment. Initial adhesion is reversible for a short period of time (59, 90), after which adhering organisms start to anchor themselves irreversibly through extracellular polymeric substance production. Coadhesion phenomena may start and finally the organisms commence to grow, with a mature biofilm as a result.