Dick Smith's Population Puzzle looks at the future of Australia's population. Tony Burke, Minister for Sustainable Population Scott Morrison, Shadow Immigration Minister Bob Brown, leader of the Greens John Elliott, former leader of the Liberal Party Tony Shepherd, Chairman, Transfield Services Dr Tim Flannery, scientist and author Dr Nikki Williams, Minerals Council of NSW Dr Suvendrini Perera, Curtin University Steve Perryman, Mt Gambier Mayor Dr Tanveer Ahmed, columnist
