The drying of wet, archaeological leather removed from a wet environment often results in a brittle, hard and shrunken material. With the correct use of freeze-drying the wet phase can be eliminated and the alteration of the leather's appearance and dimensions is minimized. Freezedrying in itself is not conservation. The process is one of dehydrating and should be combined with treatment with conservation agents. The author describes a recommended procedure: cleaning with 2-3% hydrogen peroxide followed by 10% Komplexon III, reconstruction of the object's shape, treatment with PEG 400 and Luviskol K 30 to which borax/boric acid is added, and freezing. Several methods of measurement are recommended to determine when the freeze-drying process is complete. Finally some technical and practical problems regarding the process are discussed. See also AATA 20-2331.