In order to investigate change and continuity in the concerns and practices of psychiatry in Britain during the 20th century we examined contents of the British Journal of Psychiatry. Specifically we sought to examine the paradigms used by psychiatry to conceptualize mental illness during this time. Back issues of the journal for 1 year at the mid-point of each decade were examined. We undertook a quantitative analysis categorising each article in terms of its form and content and a qualitative analysis in order to summarise the subjects that were covered. The results show that there has been continuous interest in biological aspects and treatments of mental illness with relatively little coverage of psychoanalysis or social psychiatry. Little support was found for the suggestion that major shifts have occurred in the explanatory paradigms used by psychiatry over the century. Modern interest in biological psychiatry is therefore not a new departure, but appears rather as the continuation of a long-standing inclination. The decline of the asylum-based system of care has been accompanied by a broadening in the scope of psychiatric concerns with a greater emphasis on milder mental disorders such as neurosis and depression.