Over the summer, every weekend was a 3-day weekend for Microsoft Japan employees. The company tested a 4-day workweek without reducing salaries. According to Microsoft, the result was a productivity increase of 40%. It seems that the biggest contributor to that boost is that they cut way back on meetings which, as a rule, waste a lot of time. From National Public Radio:
Because of the shorter workweek, the company also put its meetings on a diet. The standard duration for a meeting was slashed from 60 minutes to 30 — an approach that was adopted for nearly half of all meetings. In a related cut, standard attendance at those sessions was capped at five employees.
Citing the need for a shift in time management, the Microsoft division also urged people to use collaborative chat channels rather than "wasteful" emails and meetings…
Four-day workweeks made headlines around the world in the spring of 2018, when Perpetual Guardian, a New Zealand trust management company, announced a 20% gain in employee productivity and a 45% increase in employee work-life balance after a trial of paying people their regular salary for working four days. Last October, the company made the policy permanent.