Scouts BSA does have adult leaders in the form of a Scoutmaster and Assistant Scoutmaster, however Troops are Scout led.
A Senior Patrol Leader, elected by the Troop, work with his Patrol Leader Council to set the schedule for the Troop, plan outings, and plan meetings.
The Patrol Leader Council is comprised of the Senior Patrol Leader, Assistant Senior Patrol Leader, the Patrol Leaders, and oftentimes a Troop Guide and Scribe.
The adult leaders within a Troop provide counseling and guidance while allowing the Scouts to accept more responsibility and leadership.