in the driver's seat

in the driver's seat or in the driving seat

Meaning:
– in control
– in charge of things or situation

Examples:
1. The availability of a wide range of products has made the consumer sit in the driving seat.
2. Money and talent will put you in the driver's seat.
3. If you are in the driver's seat, you are in charge of something or in control of a situation.
4. I'm in the driver's seat now, and I get to decide who gets raises.
5. Destinations are limitless when your dreams are in the driver's seat.

Origin:
The first expression dates from the 1800s, the second from the early 1600s.