1. A group of 45 women suffering from "late paraphrenia" is examined. The infrequent incidence in males is mentioned.
2. The incidence of physical illness, perceptual loss, electro-encephalographic changes, the social isolation from family and community life are described.
3. An assessment is made of the constitutional factors, analysing the incidence of hereditary illness and the personality traits of the patients.
4. It is concluded that the patients suffering from late paraphrenia have a high incidence of hereditary defects and abnormal personality traits, and that stressful environmental factors late in life operate upon their biological weaknesses to produce this illness.
5. Observations were made on some beneficial effects of tranquillizers and of community care, and it is considered that life out of a mental hospital was possible for many of the patients for varying lengths of time, provided they were not demented.