Whichever method is used, paper is tested for acidity, and if this is present the document is treated with an alkaline solution. If a whole book is to be repaired it is usually taken apart. Any damaged leaves are repaired individually, and then it is re-rebound. It is usually possible, if dry methods have been employed, to re-use part or all of the old cover, or to make a new binding similar in appearance to the old. The old 'wet' repair usually made the pages so much thicker that this could not be done.
Parchment is repaired in a similar way to paper.
Large maps on paper or parchment are repaired in much the same way as smaller documents, although stronger materials, like linen for backing, have to be used. Increasingly nowadays conservators spend their time protecting documents rather than repairing them. Acid-free storage folders or sleeves are made, either from card or from an inert, clear plastic such as 'Melinex'. Special boxes are provided for books. This sort of protection, and the substitution of microfilm or photocopies for everyday use, often provide an alternative to repair for documents which are only slightly damaged or are rarely consulted.