A new technique for injecting colouring and impregnating substances into stones and porous building materials has recently been developed in the German Democratic Republic. The paper describes the procedure and the advantages of the new system, which increases penetration depth of stone preservatives about 3 to 4 times. Building materials which could be coated or impregnated using this technique include bricks, different types of concrete, stone, plasterwork and mortar, gypsum plaster, and wood. 3 bibliographic references. Photographs.