Summary: THE death has occurred in Berlin of Dr. Lydia Rabinowitch-Kempner at the age of sixty-three years. She was born at Kovno in Lithuania and studied medicine at Zurich and Berne and then in Philadelphia, where she taught in the Women's Medical College during the winter, and in the summer frequently carried out researches in Koch's laboratory in Berlin. Her first scientific work to attract attention was on the presence of non-pathogenic acid-fast bacilli in 60 per cent of the specimens of butter examined in Berlin. She then devoted her attention to tuberculosis and published articles on avian tuberculosis, spontaneous tuberculosis in domestic animals, hereditary transmission of tuberculosis in birds, etc. She also carried out researches on trypanosomiasis with Koch and on plague with Walter Kempner, another of Koch's assistants, whom she married. In 1912 she was the first woman to obtain the title of professor for scientific work. For some years prior to the anti-Semitic campaign in Germany she was editor of the Zeitschrift fur Tuberkulose and director of the Bacteriological Department of the Moabit Hospital, Berlin.