The evolution of a new pandemic strain of influenza will inevitably result in a major increase in demand for critical care services. It is likely that these services will rapidly reach their capacity and even their contingency arrangements for extended facilities will be overwhelmed. Excessive demand where resources are finite creates an ethical dilemma and many emergency plans apply a utilitarian approach of 'best care for the greatest number' [29] . There is a legitimate debate about how limited capacity can best be utilised, but a number of themes are recurrent. There needs to be a legal and ethical framework for the process decided in advance, the rationale for triage should be fair and transparent and it should meet the principles of distributive justice [30] [31] [32] . Triage can conflict with human rights legislation and even humanitarian laws but 'accountability for reasonableness' can temper the disagreements about priority setting [33] .