Patients with COVID19 present a broad spectrum of clinical presentation. Whereas hypoxemia is the marker of severity, different strategies of management should be customised to five specific individual phenotypes. Many intubated patients present with phenotype 4, characterised by pulmonary hypoxic vasoconstriction, being associated with severe hypoxemia with "normal" (>40 mL·cm-1 H20) lung compliance and likely represents pulmonary microvascular thrombosis. Phenotype 5 is often associated with high plasma procalcitonin, and has low pulmonary compliance, being a result of co-infection or acute lung injury after non-invasive ventilation. Identifying these clinical phenotypes and applying a personalised approach would benefit in optimisation of therapies and improving outcomes.