The invention provides a method of overcoming resistance to at least oneantibiotic in a multidrug resistant bacterium,said method comprising contacting said bacterium with an alginate oligomertogether with the antibiotic. The multidrug resistantbacterium may be on an animate or inanimate surface and both medical and non-medical uses and methods are provided. Inone aspect the invention provides an alginate oligomer for use together withat least one antibiotic in treating a subject infected,suspected to be infected, or at risk of infection, with a multidrug resistantbacterium to overcome resistance to the antibiotic insaid multidrug resistant bacterium. In another aspect the method can be usedto combat contamination of a site with multidrug resistantbacteria, e.g. for disinfection and cleaning purposes.
