Humanity's history is archived because of documentary sources such as records, manuscripts, books, films, and other materials. These sources, in their various forms, are fragile and prone to decay and deterioration. They need conservation and preservation. Preservation is concerned with problems such as repair, dusting, fumigation, deacidification, air-conditioning, lamination, binding, storage, etc. The principles of preservation of documentary materials in libraries, archives, and digital databases - in the light of rapid technological advances - need to be reexamined and reevaluated. This book consists of 33 papers written by scholars, experts, and practicing librarians. These contributors discuss various preservation problems experienced in their work environments, and they offer practical solutions.