This year’s global wage report explores the gender pay gap, a phenomenon which represents one of today’s greatest social injustices. Using data from about 70 countries, covering nearly 80% of wage employees worldwide, the report explores what lies behind the gender pay gap. First the report shows gender pay gaps are found just about in all countries. And on average women are paid 20% less than men across the world. And second, factors that often determine wages such as education don’t seem to explain the gender pay gap. However, our research shows that mothers are earning lower wages than non mothers. We call this the motherhood gap. We also see a tendency for wages to be lower in enterprises where the workforce is predominantly made of women. For example, in Europe wage employees in enterprises with a predominantly female workforce can earn four thousand US dollars less per year compared to those in enterprises with a similar productivity profile, but with a different gender mix. The report provides policy and recommendations that could help reduce the gender pay gap. Together with the empirical evidence we hope this contributes to the achievement of the sustainable development goal 8.5, which calls for equal pay for work of equal value in the framework of the United Nations agenda for 2030.