The article provides case studies for the conservation of water-logged archaeological leather and textiles. The materials described had been recovered from the underwater archaeological site of the <i>DEFENCE (an American privateer sunk in 1779). Modifications of existing conservation treatments for these materials are described, including the use of oxalic acid to reduce metallic encrustations, the support of leather disruptions, and the use of freeze-drying in the conservation of particularly fragile textiles.