Pippa Norris and Joni Lovenduski ask why some politicians succeed in moving into the highest offices of state, while others fail. They examine the relative dearth of women, black and working class Members of Parliament, and whether this evident social bias matters for political representation. The authors draw evidence from the first systematic surveys of parliamentary candidates, Members of Parliament and party selectors, as well as detailed personal interviews. The study explores how and why people become politicians, and the consequences for parties, legislatures and representative government.