Proceedings of a conference held at Greenwich in October, 1973. The first seven papers deal with various aspects of conservation techniques (freeze drying, fungicides, poly(ethylene glycol), acetone-rosin, the future of boat-conservation); the other six papers relate to the preservation of actual boats (Wasa, Graveney, Ferriby III). Preservation of small wooden objects is also covered, together with the use of scanning electron microscopy in fundamental research; a recurrent theme is the effectiveness or otherwise of PEG treatment.