An update is provided on the British Library-sponsored research for impregnating brittle book papers. An additional co-monomer (sic) has been incorporated to improve fold endurance after treatment; the presence of oxygen in the paper fibres inhibits significantly uptake of polymers. Nitrogen has been used to eliminate as far as possible oxygen in the treatment chambers. Treated papers have been subsequently subjected to routine procedure restoration (aqueous/not aqueous deacidification; repair with starch paste or heatset (Primal AC 72) tissue. No problems were encountered. It is hoped that eventually books on poor paper entering the library will be treated immediately thus ensuring long-term preservation. References. -- ICCROM