High medical environment in our society is related to an increase of intensive care in old patients. This situation could be looked unappropriate trying to survive people who are finishing their life. An appropriate medical evaluation and management is thus necessary in order to quantifie as fairly as possible both prognosis and specific risk. Factors at the source of mortality in elderly patients are multiple and additive. However two classes of risk can be distinguished. On the one hand some of the risk factors are intrinsic depending on the patient (i.e., neurologic impairement, age, severity of acute illness, previous health status). On the other hand some of the risk are extrinsic related to medical environment (i.e. length of stay in intensive care units, care quality...). This latter risks are improveable and thus are important to be pinpointed. Time is also powerful to assess the best prediction of outcome in old patient. Unlikely mortality rate in elderly is twofold higher (about 35%) as compared as young patients. Evaluation of intensive care unit outcome on 6 months survival make this rate worse as 10% to 20% secondary died. However most of the published studies show that duration in intensive care is similar undepending of age and outcome of the patient. It is also noted that quality of live after intensive care is the same in young or old patient. It is concluded that individual's and society's views concerning cost and effectiveness of intensive care in old patient do not always coincide with objective results. If medical motivation has to be preserved, specific care strategy remained to be established.