Unrecognised misplacement of a tracheal tube may have disastrous sequelae, and is avoidable. A variety of tests has been devised to do the prompt recognition of misplacement. The characteristic flatus-like sound produced during manual ventilation of a tube placed in the oesophagus is quite different from that produced if the tube is correctly placed, but is not reproduced reliably. Successful identification of tracheal and oesophageal ventilation has been described in small sized studies. Tests to confirm tracheal intubation are listed in this chapter. None of the easily used tests is very reliable, and haemoglobin desaturation is often the reason that bronchial intubation is suspected and detected. There are no specific tests to exclude misplacement in positions such as the retropharyngeal space or intracranial space. However there will be a complete inability to ventilate the lungs, which should become apparent very quickly using the standard tests.