Published on-line by the Congressional Research Service:

IEDs in Iraq: Effects & Countermeasures
Improvised explosive devices (IEDs) are responsible for many of the more than 2,000 deaths and numerous casualties suffered by U.S. and coalition forces since the invasion of Iraq.1 The bombs have been hidden behind signs and guardrails, under roadside debris, or inside animal carcasses, and encounters with IEDs are becoming more numerous and deadly. The threat has expanded to include vehicle-borne IEDs, where insurgents drive cars laden with explosives directly into a targeted group of service members. DOD efforts to counter IEDs have proven only marginally effective, and U.S. forces continue to be exposed to the threat at military checkpoints, or whenever riding in vehicles in Iraq. DOD reportedly expects that mines and IEDs will continue to be weapons of choice for insurgents for the near term in Iraq, and is also concerned that they might eventually become more widely used by other insurgents and terrorists worldwide. This report will be updated as events warrant.