In twenty years, the prison population, from the mother country and the overseas departments, has more than doubled, in spite of reprieve and amnesty decisions. This increase is more a consequence of longer penalties than of a rise in the number of imprisoned people The law no. 94-43, dated january 18th 1994, concerning the prisoners' medical care and welfare is an unprecedented health revolution. It comes in addition to provisions from 1986 and 1987 for the programme "13,000" prisons and those endowed with a regional medical and psychological service (SMPR). The prisoners' health must urgently be dealt with and particularly as regards infectious diseases, vaccination check-up, campaign against drug addiction health and nutrition education and dental care. As soon as incarceration has begun, the exist must be prepared and taken into consideration by the different interveners inside and outside the prison, in order to make sure of an efficient medical follow-up. As the number of intervening medical and social personnel, is increasing in prisons, a coordination inside the their walls as well as on the regional and national levels, would prove useful.