‘The Local Government Board ... is now a department of state second to none in political importance.’ So said The Times in an editorial printed in 1873, just two years after the Board’s establishment. Little known today, but mentor to, and supervisor of over 1400 local authorities across England and Wales for nearly 50 years, the impact of the Local Government Board (LGB) on the delivery and development of health and social services was deep and long-lasting. Central to this influence was its Medical Department, whose small team of doctors provided encouragement, leadership, and challenge to local authorities in their management of public health, and in particular the struggle against infectious diseasediseaseinfectious across England and Wales and beyond.