The National Target/Threat Signature Data System (NTSDS) has been designated as a migration system, in accordance with guidance from ASD(C3I) and by the Intelligence Systems Board (ISB). NTSDS provides the DoD signature data community (ISR, MASINT, & Armament) signature data from multiple, geographically distributed sites via a unified national system. NTSDS Data Centers employ standard data parameters and formats for stored target signatures for national and DoD customers.Managed by the National Ground Intelligence Center (NGIC), NTSDS is a distributed MASINT data repository and analysis system accessible using the Secure Internet Protocol Network (SIPRNET) and Joint Worldwide Intelligence Communications Network (JWICS). This distributed, federated database system links various data centers within the signature community using Netscape and Oracle applications operating on the common, secure DoD networks. As part of the development of the NTSDS, NGIC also started the Signatures Data Development Working Group (SiDDWG), a forum for MASINT data users and collectors to exchange information. The SiDDWG meets annually in conjunction with an NTSDS progress review to discuss emerging signature data collection and analysis methods and technologies. SiDDWG sessions focus on subjects such as automatic target recognition technologies and the signature data necessary to support future weapons systems. Warfighters and other users of MASINT signature data attend the SiDDWG sessions to learn more about the national capabilities available to exploit signature data.