Recent work has demonstrated that there are important continuities in theor
ies of social pathology, ranging from the 'residuum' of the 1890s to the 'u
nderclass' of the 1990s. Yet, while concepts about the 'underclass' have be
en marked by important continuities over time, there have also been importa
nt changes. This article looks at the 'problem family' of the 1950s and use
s evolving attitudes as a means of exploring the social history of social w
ork in Britain between roughly 1940 and 1970. In particular, it attempts to
look at the issue through the eyes of four different interest groups whose
members and ideas overlapped but which can none the less be considered as
having separate identities. These comprise: the Eugenics Society and other
individuals interested in eugenics, new voluntary organizations such as Pac
ifist Service Units, medical personnel including Medical Officers of Health
, and a broad coalition of academics and practitioners in the emerging soci
al work profession. The article concludes that the issue of the 'problem fa
mily' provides revealing insights into the ways in which the attitude of th
e emerging social work profession diverged from, but none the less had clos
e links with, the approach of other professional interest groups.