The TheMaS (Thesaurus Management System) is a web application used for the development of multiple multilingual thesauri, supported by a controlled decision workflow which is implemented by the assignment of discrete roles to multiple and simultaneously working users. It provides a graphical interface for building and managing multidisciplinary and multilingual thesauri, with features that provide many services, including a wide range of management functions and different modes of presentations that conform to the appropriate standards developed for thesauri building.

The thesauri management services offered by the system cover a large number of functions ranging from maintenance and expansion (i.e. addition, modification and deletion of terms, hierarchies and facets, mass import / export of terms, creation of thesauri, saving and restoring backups etc.) to the integration of multiple presentation methods (alphabetical, systematic graphical, hierarchical presentation) and access (alternative forms of navigation, support of complex search criteria, scalability search etc.).

The system also supports different categories of users that are defined by the rights provided to them. The system provides functions for managing terms, hierarchies, facets, Thesauri, database and users.