DESIGN AND METHODOLOGY: This is an open prospective multicentric study of intubation in ICU in more than 50 centres. Consecutive intubations will be included in each centre, in order to reach the sample size required (at least 1000 procedures intubations). The usual risk factors of difficult intubation in operative rooms, the demographic parameters and the complications of intubation will be assessed, as well as survival status at 28 days.