The effect of light and atmosphere on both animal and vegetable fibres is discussed. Displaying textiles in a museum often further endangers them. Active conservation of textiles is dealt with under 4 headings: 1. Removal of foreign bodies or additions; 2. Cleaning, i.e. removal of impurities; 3. Chemical treatment to strengthen the fibres (in the author's laboratory in Stockholm a water-soluble cellulose, Modocoll , is used); 4. Application of a mechanical support. The relative merits of repairing textiles bysewing and by adhesives are reviewed. -- AATA