Over the past several years, the Bárány Society has been developing an International Classification of Vestibular Disorders (ICVD) in order to standardise diagnosis and nomenclature for both clinical and research purposes. Many in vestibular practice would be familiar with the symptoms of orthostatic dizziness. Haemodynamic orthostatic dizziness/vertigo incorporates conditions such as orthostatic dizziness/vertigo, postural dizziness/vertigo, exertional dizziness/vertigo and presyncopal dizziness because haemodynamic changes underlie all of them. To diagnose haemodynamic orthostatic dizziness/vertigo, the following three criteria must be fulfilled: A) Five or more episodes of dizziness, unsteadiness or vertigo triggered by arising (i.e. a change of body posture from lying to sitting/standing or sitting to standing), or present during upright position, which subsides by sitting or lying down; B) Orthostatic hypotension, postural orthostatic tachycardia syndrome (POTS) or syncope documented on standing or during head-up tilt test; and C) Not better accounted for by another disease or disorder. For probable haemodynamic orthostatic dizziness/vertigo, criteria A and C are applicable but B is different, i.e. at least one of the following accompanying symptoms: generalised weakness or tiredness, difﬁculty in thinking or concentrating, blurred vision, tachycardia or palpitations. The authors discuss in great detail the features of all the conditions which have been incorporated under this one diagnostic entity as well as differential diagnoses. They stress the distinction between this diagnosis and benign paroxysmal positional vertigo (BPPV) and persistent postural-perceptual dizziness (PPPD). In my view, the clinical utility of this diagnostic entity would probably be limited because once the diagnosis is made, treatment would depend on the underlying condition, in effect taking apart the components the diagnosis. However, the detailed notes and comments on the various haemodynamically-mediated conditions are worth reading.