A shorter working week is worth piloting, not just debating

Arguments about a four-day week usually run on instinct: supporters say people will be healthier and just as productive, critics say output will fall and costs will rise. We think the productive move is to stop arguing and start measuring.

A four-day week generally means working roughly 32 hours over four days, often with no cut in pay, though definitions and arrangements vary. Several organisations and governments have run trials, and long-run data show that working hours have fallen over time in many countries as economies have grown. What matters is how a change works in a particular sector: a hospital, a factory and a software company have very different constraints.

Our view is that pilots with clear measures, such as output, quality, customer satisfaction, sickness absence and staff turnover, and with a pre-agreed way to decide whether to continue, are a better guide than slogans.

What would change our mind: well-run trials, across many kinds of workplace, that show consistent harm to output or to workers' well-being.

A good pilot publishes its method before it begins.