The resilience of health systems has never been so important with the increasing frequency of extreme climate events, mass migration, economic crises and pandemics. This paper examines what strategies can build resilience; the central role of workforce in resilience before, during and after shocks; and whether migrant labour makes health systems more resilient or more vulnerable. The importance of sufficiency, flexibility and motivation / engagement, in relation to resilience building, are discussed within the context of a global shortage of health care workers and a profound demand and supply imbalance between high and low-middle income countries. The question of whether health system resilience can be bolstered by migration is nuanced. Governments who rely on health worker migration need to set robust policies, manage migration in a constructive way and adopt formal agreements for which they are accountable.