The syndrome of hyperventilation attacks in the company of anxiety has been discussed often in the litterature. After longer periods of stress or after short periods of extreme anxiety a vicious circle of hyperventilation, symptoms and anticipation anxiety — again leading to hyperventilation — is easily established. Once this vicious circle is firmly established, fobias, mainly agorafobias, may result. The authors describe a method for the diagnosis and treatment of this syndrome, which relies on the provocation of hyperventilation attacks. This procedure is discussed from a standpoint based on learning theory and communication theory. The authors offer that this form of treatment may be helpful in the prevention of fobias, and in cases where further psychotherapy is indicated the method described may serve as a good introduction to the psychotherapy.