Further to the arrival of large influxes of migrants at Greece's land and sea borders, the Greek Government invited the WHO Regional Office for Europe to organize a joint mission between 15 and 19 December 2014 to assess health system capacity to manage large influxes of migrants. The mission aims were threefold: to assess the ongoing pre- paredness and response activities of the local health system; to plan ad hoc technical assistance if required; and to pilot the draft WHO toolkit for assessing health system capacity to manage large influxes of migrants in the acute phase. The members of the assessment team undertook site visits at first reception centres and pre-departure facil- ities, and conducted interviews with all key stakeholders. From their findings, their main recommendations include improvements in living conditions in migrant centres, the preparation of a national multisectoral contingency plan, a harmonized health data collection system and a strengthened migrant immunization policy.