Method and apparatus for sterilizing containers with a sterilization medium. The method involves first introducing a sterilization medium into a container, and then introducing a heated gaseous and/or vaporous activation medium into the container. The activation medium is used to heat and activate the sterilization medium to destroy microorganisms. At least one parameter of the method is controlled based on the detected temperature of the container or the wall of the container. Alternatively, the heating and activating of the sterilization medium is achieved by first introducing an activation medium into the container under time control at a constant temperature and at a first, constant, volume flow, and then subsequently adjusting to a second, different, volume flow.
