Abstract: The invention provides a solid lavatory cleansing block formed of a composition comprising (A) from 5% to 80% by weight of a surface active component comprising one or more anionic surface active agents; (B) from 10 to 75% by weight of a chlorine release agent component consisting of one or more chlorinated cyanuric acid derivatives and chlorine agents; and (C) from 2 to 25% by weight of a solubility control agent (as hereinbefore defined); the composition containing not more than 20% by weight of water-soluble inorganic salt introduced with the anionic surface active agent component and containing no other added fillers or diluents.