1st Marine Expeditionary Brigade is a unit in the I Marine Expeditionary Force (I MEF) and is the "middleweight" crisis response force of choice in the European and Southern Command Areas of Operation. It is able to "operate independently, as a service component, or to lead a Joint Task Force".
Command Element - Battalion equivalent headquarters organization, formed of companies/detachments sourced from the parent MEF HQ Group and staff, and with the Deputy MEF Commander as the MEB Commander.
Ground Combat Element - Regimental Combat Team (RCT) consisting of a reinforced Marine Infantry Regiment.
Aviation Combat Element - Marine Aircraft Group (MAG), consisting of a combination of rotary-wing, tiltrotor, and/or fixed wing aircraft squadrons/detachments and aviation support squadrons/detachments, capable of conducting all (6) functions of Marine aviation including offensive air support, assault support, electronic warfare, control of aircraft and missiles, anti-air warfare and Aerial Reconnaissance.
Logistics Combat Element - Combat Logistics Regiment (CLR), consisting 1 to 3 Combat Logistics Battalions (CLB) and capable of providing full-spectrum Combat Service Support to all elements of the MEB.