NSIS

NSIS may refer to:

Technology

 * National Sheep Identification System, the implementation in Ireland for the identification and registration of ovine and caprine animals
 * Network Store Interface Service, a Microsoft Windows service
 * Next Steps in Signaling, a former Internet Engineering Task Force working group
 * Nullsoft Scriptable Install System, a script-driven Windows installation system

Other uses

 * National Strategy for Information Sharing, part of Nationwide Suspicious Activity Reporting Initiative
 * National Security Intelligence Section, of Ireland's Directorate of Military Intelligence