Commencing in 1893, Rüdin studied medicine at universities in several countries, graduating in 1898. At the Burghölzli in Zurich, he worked as assistant to Eugen Bleuler who coined the term 'schizophrenia'. He completed his PhD, then a psychiatric residency at a Berlin prison. From 1907, he worked at the University of Munich as assistant to Emil Kraepelin, the highly influential psychiatrist who had developed the diagnostic split between 'dementia praecox' ('early dementia' – reflecting his pessimistic prognosis – renamed schizophrenia) and 'manic-depressive illness' (including unipolar depression), and who is considered by many to be the father of modern psychiatric classification. Rüdin became senior lecturer in 1909, as well as senior physician at the Munich Psychiatric Hospital, succeeding Alois Alzheimer.