Abstract: Disclosed is a method for killing spores from a surface or a material, comprising applying an effective amount of a biocidal composition which comprises one or more biguanide polymers, and one or more further active agents on said surface or material, characterised in that the or each further active agent is, when taken alone, sporicidally inactive. Compositions comprising polymeric biguanides and one or more further biocidal agents and, optionally, a polyorganosiloxane, have been found to be effective as a sporicidal agent and are particularly effective against the spores of C. difficile. The compositions may be used in industry, in domestic applications and are particularly suitable for use in hospital due to their low toxicity. Furthermore, the method may comprise impregnating a fabric to thereby provide long lasting sporicidal activity thereto.