Gender equality has been enshrined in the Swiss constitution for more than 40 years. Despite this, unexplainable wage differences between men and women persist. Swiss efforts to close these gaps are attracting global attention, particularly in places where wage differences are large. An international study spanning 15 well-off countries shows that there are pay gaps between men and women of the same age, with the same level of education, and in jobs with the same part-time conditions. This difference cannot be explained solely by the fact that women tend to work in lower-paid professions. Women are also paid less when working for the same employer and in the same role as their male colleagues. This "unexplained" part of the pay gap accounts for more than half of the difference between men’s and women’s wages in many countries. Take Japan for example, where the gender pay gap amounts to almost 35%. Part of that difference can be explained but around 25% cannot. Therefore, it comes ...