take charge
take charge {v. phr.}
To begin to lead or control; take control or responsibility; undertake the care or management (of persons or things).
When Mrs. Jackson was in the hospital, her sister took charge of the Jackson children until Mrs. Jackson could care for them.
The child care class gave a party for the nursery children, and Mary took charge of the games.
John was elected the new president of the club and took charge at the next meeting.
Bob is a natural leader, and can take charge in an emergency.
Compare: IN CHARGE (2).
Categories:
Source: A Dictionary of American Idioms