The GHS Index conceptualises a health security capacity as a state’s ability or potential to carry out a discrete public health or healthcare function necessary to prevent, detect or respond to acute infectious disease threats, be they naturally occurring, accidental or deliberate. Featured indicators in the GHS Index are intended to aid users in monitoring and measuring the investments and processes that enable states to build, sustain and implement these capacities. The GHS Index does not, however, purport to forecast health outcomes or impacts resulting from country investments in strengthening health security capacities.