COVID-19 is now a global pandemic. As cases rise rapidly, one effect will be to raise deep and troubling ethical issues. If the UK follows Italy, as it is predicted to, one such ethical issue will be an extreme demand placed on healthcare resources, specifically intensive care. Indeed, given differences in ICU beds it may well be that the challenges facing the NHS exceed those seen in Italy. Effective triage is the appropriate response to ensure that in spite of a severe mismatch between supply and demand allocation of resources is fair. In an overwhelmed system with critically unwell patients, doctors must decide which patients get oxygen, intensive care, both, or neither.