 Each panelist writes an introductory column with their take on the week's topic which acts as a springboard for further discussion.Until 2006 the series was presented by Matthew Parris, who has moved on to Radio 4's biography series "Great Lives".He was succeeded by Dominic Arkwright, a radio reporter for the "Today" programme who has covered conflicts in Afghanistan, Mozambique, Nagorno-Karabakh, Kashmir and Kosovo among others.