The Improvised Explosive Device (IED) threat faced by coalition partners in Iraq and Afghanistan required concepts of operations to identify threat actors, network analysis to attack the network, and counter-IED strategies to defeat the devices. Forensic science was employed beyond its traditional law enforcement investigation and criminal justice objectives, and provided a capability for military organizations to help to counter IEDs. Forensic science in support of the expeditionary force on the battlefield is referred to as expeditionary forensic science, which is not well understood outside of the military domain. Military forensic science could be considered the black sheep of the forensic family as it is often left out or not considered alongside traditional forensic science. The purpose of this paper and plenary address, presented at the Australian and New Zealand Forensic Science Society (ANZFSS) 24th International Symposium, is to provide the broader forensic science community with a better understanding of military expeditionary forensic science. The aim is to promote greater partnerships between law enforcement, intelligence, the criminal justice system, and military forensic science as part of the broader forensic science ‘system of systems’. Abbreviation: System of systems (SOS); improvised explosive devices (IED).