While most nations are dependent to some extent on the world’s 214 million migrants for skills and labour, few ensure these migrants have access to their health systems, something that could have dire public health consequences, according to the International Organisation for Migration (IOM). Describing migrants’ lack of access to health services as 'one of the biggest challenges facing global health today', IOM marked International Migrants Day on 18 December by calling for more migrant-inclusive health policies.