Three different Combat ID systems for the Dismounted Soldier are described and areas of commonality and differences are noted. CIDDS (Combat ID for Dismounted Soldiers) is a complete Stand-Alone system for non-Land Warrior equipped soldier's. To the weapon, it adds a laser interrogator that produces a Multiple Integrated Laser Engagement Systems (MILES) like pulse coded waveform and a RF receiver. To the soldiers helmet, it adds four laser detectors and an RF transmitter that uses frequency diversity and TDMA to respond. Land Warrior Combat ID, being developed on the Force XXI Land Warrior program, adds a similar laser interrogator to the weapon but uses existing laser detectors on the helmet. Detection of a laser interrogation automatically causes a RF reply via the Land Warrior Soldier Radio (LWSR) that operates in the 1.8 GHz frequency range using a TDMA format. Helicopter to Dismounted Soldier ID (HDSID) uses the SIngle Channel Ground Airborne Radio System (SINCGARS) SIP+ radios, operating in the 30 to 88 MHz band, for both interrogation and reply. The SINCGARS SIP+ ground receivers interrupt normal voice or data transmission/reception every second for a very short interval and switch to receive on the 'Interrogation' net. Up to three helicopters can make interrogations during any one-second interval. CIDDS and Land Warrior CID are presently in development, while HDSID is a recently completed study.