As Hillary Clinton becomes the official Democrat candidate for US President, with aim of becoming the first woman to take that role, Jonathan Freedland takes the long view of pioneering women politicians, examining how Nancy Astor became the first woman to take her seat in the House of Commons - in a constituency previously represented by her husband. Astor faced intense press scrutiny, and a presumption that she should focus on issues such as child welfare - but she also enjoyed the renown of the Astor name.

With historians Jacqui Turner and Gary Gerstle, political commentator Kate Andrews, Christiane Amanpour from CNN, Melanie Unwin, deputy curator of the Parliamentary Art Collection and Mari Takayanagi, archivist at Parliament. The reader is Kathy Clugston.