Medical (clinical) waste has a similar or posssibly lower content of microorganisms than household waste. There is no evidence of transfer of infection from waste, apart from needlestick injuries to hospital staff where the risk of HIV transfer is low. Chemical and heat methods of decontaminating medical waste are described, but the necessity for destruction or decontamination before disposal is doubtful. Categories of medical waste based on infection risk are proposed. More attention should be focused on reducing the total volume of waste, recycling and more use of reprocessible items.