Existing data on social mobility in Britain demonstrate a disparity of
up to 4:1 in the relative chances of children from different social c
lass backgrounds ending up at the top or bottom of the occupational cl
ass system. In an earlier paper, it was argued that such disparities s
hould not necessarily be seen as the result of social advantages or di
sadvantages associated with different class origins, fbr they are also
consistent with a model of meritocracy in which class differentials i
n average levels of ability are reflected in the class destinations ac
hieved by people from different social backgrounds. That paper has bee
n criticised, both analytically and empirically, and this paper addres
ses some of these criticisms through an analysis of data from the Nati
onal Child Development Study. The analysis shows that ability is an im
portant factor influencing social mobility chances, and through a seri
es of logistic regression and multiple regression models, it demonstra
tes that meritocratic factors (individual effort and ability) outweigh
social advantage/disadvantage factors in predicting the occupational
class achieved by over 6,000 men and women by age 33. The paper ends b
y answering the analytical criticisms made against the earlier paper.