This book is about the political, economic and moral salience of social mobility in Britain today. The way that, and the extent to which, people move or fail to move from one position in society to another – up or down the social hierarchy, through education and employment – is one of the central processes in contemporary society. It involves issues of inequality in individuals’ opportunities to use their talents in our society, the fairness and legitimacy of social and political status quo, and the effective use of the country's most basic resource: its people. Not only are differential mobility opportunities a form of social inequality in themselves, but belief in the future prospect of potential improvement – at least for one's children – and thereby in the legitimacy of mobility can make current social inequities easier to bear.

Social mobility is also one of the most misunderstood processes of our time.

This is ironic, because social mobility has been moving up the political agenda since the turn of the century at an astonishing rate, with media coverage increasing literally tenfold in the last decade (see chapter Three). In 2014, a report observed how: ‘in recent years government has introduced a number of initiatives to improve social mobility and a Social Mobility and Child Poverty Commission (SMCPC) has been created to monitor progress in this area right across government policy … a clear indication of broad political support’ (Brown 2014, 9).

Immediately before this book went to production, the European Union (EU) referendum and its result blew regular political issues away. But all five of the Conservative leadership candidates except for Andrea Leadsom invoked social mobility in their campaign launch speeches (Fox 2016; Gove 2016; Johnson 2016; May 2016a); May's inaugural speech as Prime Minister highlighted pledges to improve opportunities for everybody to go as far their talents could take them (May 2016b). However, because of its complex nature, understanding social mobility and its social significance has challenged public commentators and non-specialist academics alike.

The result has been too much loose talk about ‘needing more mobility’ without clarity about what mobility means or what its consequences might be. Although in common parlance mobility is generally seen as a comparison across generations – between a person's family background and his or her adult career achievement – there has been a perhaps inevitable lack of precision in the definitions implicit in public debate.