Hundreds of students and young executives from all over the world take part in the annual Drucker Challenge essay contest, and the winners are heralded at the Drucker Forum. This years' theme was Human Prosperity in a Changing World. Four of the winners talk to Peter Day about their experiences, and their ideas. They are Anne Twombly from the USA; Ali Rushden Tariq, born in Pakistan but now living in Canada; Amina Mendez Acosta from The Phillipines, and Chris Maclay, born in the UK, now living and working in Kenya.