Addresses are held throughout the year and represent a fabulous opportunity to listen to and ask questions of some of Britain's leading figures. They usually consist of a short speech on specific topic which is then followed by a question and answer session. Notable addresses within the last few years include star of stage and screen Patrick Stewart; former Foreign Secretary David Miliband; Deputy Prime Minister Nick Clegg,  former head of the armed forces and commander of the SAS Gen. Lord Guthrie; former Taoiseach Bertie Ahern, former London mayor Boris Johnson; Harry Potter star Imelda Staunton; boxing supremo Frank Bruno; Monthy Python actor Michael Palin; film director Michael Winner; journalist, war correspondent and former independent MP Martin Bell; newsreader Jon Snow; met chief Sir Ian Blair; bestsellling author Will Hutton; Green Party leader Caroline Lucas; film critic Barry Norman; world leading expert on genetics Prof Lord Winston; and BBC presenter Jeremy Vine.