Of the 452 people who died at home in Paris between August 1 and 31, 2003, and were transported to the Medicolegal Institute (IML), 92% died between August 1st and 20th. This study is based on investigations carried out at the discovery of the body, and on the results of medical examinations performed at IML. Half the study population were over 80 years old, and 88% lived alone, half of them in top-story single rooms. More than 70% had medical antecedents, cardiovascular disorders and psychological disorders. Three-quarters had forerunner symptoms. The extreme vulnerability of these people makes them the prime target for prevention.