‘Why migration matters’ shows why the topic of migration is important in the modern world. Migration began when Homo erectus and Homo sapiens moved out from the Rift Valley and colonized Eurasia. The process continued for centuries after, with several major migration events in the past 300 years. According to the UN, one in every thirty-five people is a migrant, but migration affects far more than that. The number of migrants has doubled in the past twenty-five years, with numbers of female migrants growing particularly quickly. Despite the positive effects of migrant labour, problems still exist for both the host and donor countries, and the migrants themselves.