Syndicat Intercommunal d'Informatique (SII)

The Syndicat Intercommunal d’Informatique (SII) is a public IT service provider that delivers shared technology solutions to municipalities and other local public entities in France. Its core offerings include the operation and maintenance of municipal applications such as email systems, family portals, school and BAFA registration platforms, and invoice distribution services. In addition, SII hosts websites for affiliated organisations, including inter‑municipal bodies like the catering union Siresco, and supports public housing offices and other community services. By pooling resources across multiple communes, the syndicate enables its members to access reliable IT infrastructure without each having to develop and maintain separate systems.

SII serves a network of municipalities primarily located in the Seine‑Saint‑Denis department, with documented clients including Tremblay‑en‑France, Le Blanc‑Mesnil, La Courneuve, and Bobigny’s public housing offices. As an intercommunal syndicate, its organisational structure is designed to collective governance, allowing member communities to jointly oversee IT strategy and service delivery. The syndicate’s reach extends beyond basic support to include incident response and recovery coordination, as demonstrated by its collaboration with municipal IT teams during cyber events to restore critical functions and implement regulatory measures.

A distinguishing attribute of SII is its specialised focus on providing secure, compliant IT services to the public sector, positioning it as a key enabler of digital administration for local government. The organisation has demonstrated its role in managing cybersecurity incidents, notably responding to a ransomware attack by the Hive group in December 2021 and a broader cyberattack in March 2023 that disrupted services such as email processing and registration portals. These events underscore SII’s responsibility for maintaining operational continuity and its involvement in post‑incident containment, recovery, and the implementation of safeguards across the municipalities it supports.