Intergenerational mobility is about the relationship between people’s outcomes and their childhood family circumstances. Researchers have sometimes defined intergenerational economic mobility as being about the extent to which an adult’s income and occupation are determined by their own talents and ambition, irrespective of their family background (Blanden, Gregg and Machin, 2005, p.2). This type of intergenerational mobility differs from the structural mobility that happens when average incomes and job quality improve over time, and is sometimes also different from the intragenerational mobility that occurs when individuals change jobs or advance in their career (Aldridge, 2005). Because of social and political interest in equality of opportunity and economic efficiency, intergenerational economic mobility has been of increasing interest to researchers.