U.S. Army Soldier from the 54th Brigade Engineer Battalion of the 173rd Airborne Brigade, provides security during Immediate Response 15 in Slunj, Croatia. Immediate Response 15 is a multinational, brigade-level, Command Post Exercise utilizing computer assisted simulations and field training exercises in Croatia and Slovenia.The exercises and simulations are built upon a decisive action based scenario and are designed to enhance regional stability, strengthen partner capacity and improve interoperability.