The present application relates to apparatus for generating steam. The apparatus comprises an evaporation surface (24), a heater (26) disposed adjacent to the evaporation surface to heat the evaporation surface, a water inlet (19) positioned relative to the evaporation surface so that water is fed onto the evaporation surface from the water inlet and forms a film on the evaporation surface such that the film is evaporated from the evaporation surface, and a scale collection region (23) positioned such that, during use of the apparatus, scale dislodged from the evaporation surface falls away from the evaporation surface into the scale collection region. The apparatus is configured so that the flow of water through the water inlet (19) and onto the evaporation surface (24) is controlled in dependence on the temperature of the evaporation surface (24) so that substantially all the water fed onto the evaporation surface is evaporated from the evaporation surface without flowing from the evaporation surface into the scale collection region (23).