The collection of tablets in the British Museum is the largest single collection in the world and is being augmented annually. Most tablets are of unbaked clay containing water-soluble salts which tend to migrate to the surface of the clay as a result of the natural changes in ambient relative humidity during storage. Here the salts crystallise out and may obscure and damage the inscription. Treatment involves baking at 75° C in order to make the tablets resistant to water, followed by thorough washing in order to remove salts. The need to treat a very large number of tablets (up to 10,000 per year) made it necessary to plan a workshop on factory lines and the equipment and procedures are described.