This document provides an overview of the European Security System (ESS), which is a portable, scalable, ad-hoc system that uses various sensors to provide improved crisis management and decision support during emergency events. Funded by the European Union for 48 months from 2009-2013 with a 9.1 million euro grant, the ESS coordinates data from end users like law enforcement and first responders with research institutions and industry partners to create a common operating picture during disasters. It allows for quick deployment, independence from infrastructure, and flexibility depending on the needs of the crisis. The ESS enhances command and control and aims to minimize uncertainty during unpredictable events like natural disasters, CBRN incidents, or terrorist attacks through its mobile command centers and