Digital pioneer Martha Lane Fox delivers 2015's Richard Dimbleby Lecture.
Christine Lagarde explains her thinking on the challenges facing the global economy.
Philanthropist Bill Gates explains his optimism for a world free of polio.
Leading geneticist and Nobel laureate Sir Paul Nurse explores the wonder of science.
Children's author and campaigner Michael Morpurgo gives the 35th Dimbleby Lecture.
Author and Alzheimer's sufferer Sir Terry Pratchett gives the 34th Dimbleby Lecture.
His Royal Highness The Prince of Wales gives The Richard Dimbleby Lecture.
Gene pioneer Dr J Craig Venter gives the 32nd Richard Dimbleby Lecture.
General Sir Mike Jackson gives the 31st Richard Dimbleby Lecture.
Director General Stella Rimington sheds light on the workings and basic remit of MI5.
Lord Rothschild discusses the assessment and acceptibility of risks.
David Dimbleby introduces Lord Hailsham's lecture, in which he proposes political reform.
Former managing director of BBC television, Sir Huw Wheldon, gives a lecture.