The Marine Expeditionary Unit Service Support Group 15 (MSSG-15) was a logistics unit within the United States Marine Corps, primarily tasked with providing combat service support to the 15th Marine Expeditionary Unit (MEU). Established to enhance the operational reach and sustainability of the 15th MEU, MSSG-15 participated in numerous deployments, including humanitarian missions and combat operations such as Operation Enduring Freedom and Operation Iraqi Freedom in the early 2000s. The unit excelled in delivering supply, maintenance, transportation, health services, and other critical support functions during amphibious and expeditionary missions. In 2006, MSSG-15 was redesignated as Combat Logistics Battalion 15 (CLB-15), reflecting broader changes in Marine Corps logistics structure.