Authors provide detailed information about the process of preparing books for mass deacidification of library collections in the National Library of the Czech Republic, as well as in other institutions of the Czech Republic. We present the basic principles of deacidification and the requirements for the ideal method of mass deacidification of books. This includes the selection of mass deacidification technology, the preparation of books for deacidification, the methods of testing the quality of deacidification, checking after deacidification, etc. The article is supplemented by a clear diagram of the workflow used for the implementation of massdeacidification of library collections and a list of literature on the topic.