As of the understanding that there is at some point the need to exist the disposal of materials in libraries, this book has as one of its main objectives the verification of stages and criteria concerning the development of collections, especially the disposal, targeting public libraries of Rio Grande do Sul. Through the analysis carried out, it was concluded that there are librarians in most of the public libraries questioned, however there are still few that have a formal document indicating guidelines or procedures that serve as guidance and support for the development of collections, however even so there is the disposal in these institutions. It is believed that as the subject of disposal of materials in libraries is somewhat sensitive and difficult to deal with given the difficulty that professionals have in doing so for numerous reasons, throughout the text it was proposed paths for the development of collections showing that the cycle does not happen randomly, but rather through procedures step by step and that each library must have its own guidelines being necessary the existence of a plan.