Mark Lowcock leads global humanitarian relief efforts for the UN. Mark's optimism has sustained him throughout his 30-year career delivering aid to people suffering from war, poverty and famine.

"One of the things I hold on to is most people on the planet have escaped from those problems, as the generations have passed. And when you're confronting the next bleak, horrible event, holding on to the fact that it's possible to escape…is invaluable."