To bring about means to cause something to happen or to make something occur. When a scientist's discovery brings about a new medical treatment, her work has caused that breakthrough to exist. When a student's honest conversation brings about a positive change in the classroom, their courage has made that improvement happen.

The phrase emphasizes taking action that leads to a result. A peacemaker might bring about an agreement between arguing friends. A determined inventor might bring about a solution to a problem that has frustrated people for years. Historical figures like Benjamin Franklin helped bring about American independence through their words, actions, and persistence.

You can bring about both small and large changes. Practicing every day can bring about improvement in your piano playing. Speaking up when you notice something unfair might bring about a better rule. The phrase emphasizes that someone or something has actively caused a result, rather than just hoping for it or waiting for it to occur on its own.