If you are in charge (of), you have control over someone or something and are responsible for them

Who’s in charge here?

Philip’s in charge of our marketing department.

She is in charge of hiring new employees.

The teacher put me in charge of organizing the project.

They are also in charge of purchasing and using new equipment and techniques.

The person in charge should do something.

Ask to speak to the person in charge.

Some situations require the person in charge to make the final call.