About 70 companies are taking part in what is thought to be the world's biggest pilot scheme into the working pattern over the next six months. The experiment has been organised by a group campaigning for a shorter working week, but for no loss in wages. During the trial, employees will get 100% pay for 80% of the hours they would usually work, with the aim of being more productive. Academics from Oxford and Cambridge universities, as well experts at Boston College in the US, will manage the experiment in partnership with the think tank Autonomy. Companies ranging from office-based software developers and recruitment firms to charities and a local fish and chip shop are taking part. The UK trial is historic", said Juliet Schor, the lead researcher on the Global 4-day week project. "The basis of this movement is that there's activity going on in many workplaces, particularly white collar workplaces, that's low-productivity and that you can cut without harming the business." She said the trouble with the five-day week is that work can simply expand to fit the time available. "Sticking to a rigid, centuries-old, time-based system doesn't make sense," Ms Schor added. "You can be 100% productive in 80% of the time in many workplaces, and companies adopting this around the world have shown that." Even if workers are just 10% more productive the economics can still stack up, she argued, if it leads to lower sickness rates, fewer staff leaving and making it easier to attract new recruits.