This book had its beginnings in 2003 when Harry Duynhoven, a Member of the New Zealand House of Representatives, made an application for a Dutch passport and inadvertently triggered his disqualification from Parliament as a result. Although Mr Duynhoven was saved by a retrospective suspension of the offending law, the episode sparked my interest in just how members of the legislature not only obtain their seats and remain there: how would the representative’s entry to and exit from Parliament be decided, and what sort of people do we want as our representatives? The bulk of this work was completed as my doctoral thesis at King’s College London, where I benefited from the kind and expert supervision of Professors Robert Blackburn and Keith Ewing. In addition Dean Knight, David Monks, Graeme Orr and Bob Posner read various chapters and contributed valuable comments and insights. Of course any errors that remain are my own. Richard Hart and Rachel Turner of Hart Publishing were enthusiastic and efficient as my thesis metamorphosed into this book: the perfect combination in an editorial team. I am also grateful to my former colleagues in the legal team of the UK Electoral Commission: Bob Posner, Elizabeth Morrow, Rosie Sidey and Michelanne Calhoun Wilson, with whom I spent a very enjoyable six months in 2008–2009 at the electoral law coalface. None of the views expressed here should be taken to have the endorsement of the Electoral Commission. My thanks too to Yana Geary of Victoria University of Wellington and Katelyn Schoop of Queen Mary, University of London, for their meticulous and patient work in formatting and re-formatting the manuscript, hunting down my typographical errors, and generally correcting the errors of my word-processing ways. And lastly, to my husband, Richard Searle: thanks – for everything.