be in control

1. To possess the ultimate authority in a hierarchy or situation; to be in charge. Who's in control here? I want to talk to the ranking officer. The Saints seemed to be firmly in control for the first 30 minutes of the game, but then the Chargers evened the score in the third quarter. Yeah, I don't think the nanny is in control if all the kids are running around screaming.

2. To be confident and capable, often when faced with a stressful situation. Your mother was terrified when she first learned to drive, but now she is completely in control behind the wheel. You need to be in control of the interrogation—don't let the suspect dictate the conversation. Ben gets a little keyed up before he goes on stage, but once he's out there, he's completely in control.

be in conˈtrol (of something)

be able to organize your life well and keep calm: In spite of all her family problems, she’s really in control.