Platoon Sergeant
The Platoon Sergeant is responsible for all the enlisted Marine personnel assigned to his/her Platoon Commander's platoon. The Platoon Sergeant is usually the senior enlisted Marine in the platoon.
Usually a Platoon Sergeant holds the rank of Staff Sergeant although it can be held by a Sergeant or even Gunnery Sergeant.
The Platoon Sergeant works closely with the Platoon Commander, supervising the training of the men in their platoon. Generally the Platoon Sergeant has years of experience and are often very respected by their soldiers and superiors. The Platoon Sergeant can also fill in for a Platoon Commander should they be killed or wounded, unless there is a higher ranking NCO who can take the position.
The Platoon Sergeant reports to their Platoon Sergeant as well as their Company Sergeant or First Sergeant.