Ustka, Poland (June 10, 2004) - A German Army rifleman uses a dummy grenade to assault a room during "glass-house" training. A glass house is an imaginary house outlined with tape, and enables fire teams to be closely monitored on their tactical skills, prior to actual engagement. BALTOPS is an individual combined maritime and land exercise in the Baltic Sea, conducted "in the spirit of" Partnership For Peace (PFP). The operation runs from 07-19 June 2004 and includes NATO and non-NATO participants. The mission of BALTOPS 2004 is to promote mutual understanding, confidence, cooperation, and interoperability among forces and personnel of participating nations and support national unit/staff training objectives through a series of robust training exercises.