Purpose: This study aims to clarify the management structure of special libraries with full-time outsourcing. Based on these results, it also proposes what is necessary in order to maintain and improve library services and improve the treatment of contract workers. Methods: Interviews were conducted based on the actual conditions in nine libraries which have full-time contract workers. Results: Our investigations revealed three trends: (1) The management of the system is shared by the entruster, the contractor, the contract workers, and the host organization. (2) Special libraries operate under two conditions: ones common to almost all the libraries, and others that are unique to some. Some of the former and all of the latter seem to be necessary for the general management of full-time outsourcing. (3) There are two typical forms of management: entruster-centered and contract worker-centered. We reached the following conclusions. First, in order to maintain and improve the library's services, the entruster should take a position of leadership in libraries with full-time outsourcing. Reasonable limits should be set on the contents of the work done by contract workers; planning and selection of materials should be excluded from these contents. In addition, the contractor should make every possible effort to understand the library's operation, and offer professional development opportunities to the contract workers. Second, in order to improve the treatment of the contract workers, entrusters must enter into contracts with the contractors at a fair price, giving careful consideration to the contract workers' professional abilities. Contractors should offer workers a better salary based on an increase in the contracted rate. And moreover, the general public should restrict the contractors' permitted profit margins and gain further knowledge of the equal treatment doctrine. [ABSTRACT FROM AUTHOR]