Diversity is evident in the different routes that women take through motherhood. Around one in seven White mothers are bringing up children as lone mothers. Among African and African-Caribbean mothers the proportion is higher; however, only a relatively small proportion of mothers from other Black minority ethnic groups are lone parents (Haskey, 1991a) . The evidence suggests that for many White and Black women lone parenthood is a temporary rather than a permanent status : the average duration of lone motherhood for an unmarried woman, for example , is three years (Ermisch, 1989) . The movements into and out of lone motherhood suggest that the increase in the numbers of lone mothers is due less to more women choosing a different, but relatively fixed, domestic arrangement. It is more the result of an increasing number of women building and rebuilding different kinds of family units as they move through motherhood.