Conceived by Sir David Attenborough in 1967, Natural World is the longest-running nature documentary series on British television. 2008 marked the series’ 25th anniversary under its present title, though its origins can be traced back to its predecessor The World About Us which began over 40 years ago. Natural World is broadcast on BBC Two in the autumn and spring seasons, with 17 episodes commissioned by the BBC each year. Production duties are shared between its in-house Natural History Unit, independent UK production companies and leading wildlife filmmakers from around the world.