To step up

You can step up, step down and sidestep! You step up when you agree to take on a new responsibility, you step down when you decide to stop doing a particular role and you sidestep an issue you don’t want to discuss by ignoring it!

Examples

“Are you going to step up and be the new leader of the scout group?”

“It’s about time the prime minister stepped down. He’s made so many mistakes!”

“My boss always sidesteps the fact that we’re not making enough money. I’m worried the company will do under.”