Arianna gave a speech about the Third Metric at the 2013 One Young World Summit last week. The summit was held in Johannesburg, South Africa.
"It is incredibly important that while you go out and change the world, you take care of yourself," she said.
We need to redefine success, she said, so that success is defined by personal wellness as well as professional achievements.
"We are leading lives that are not sustainable,"she said.
Watch the full speech above.