Four-day work week

The contemporary four-day work week movement operates primarily on a model known as 100-80-100, in which employees receive one hundred percent of their pay for eighty percent of the hours, in exchange for maintaining one hundred percent of their productivity. The concept has older roots, with individual companies experimenting with compressed schedules since at least the 1970s, but the coordinated trial model emerged in the early 2020s through the nonprofit 4 Day Week Global, founded by Andrew Barnes and Charlotte Lockhart after Barnes's own company, Perpetual Guardian in New Zealand, ran a successful trial in 2018.

The UK pilot, coordinated by 4 Day Week Global in partnership with researchers from Cambridge University, Boston College, and the think tank Autonomy, ran from June to December 2022 across sixty-one companies employing roughly 2,900 workers. The results, published in 2023, reported that revenue across participating firms remained stable or grew during the trial period. Employee well-being improved significantly, with reported reductions in burnout, anxiety, and sleep problems. Fifty-six of the sixty-one participating companies chose to continue the four-day week after the pilot ended, with eighteen adopting it permanently.

Similar trials have been conducted in Iceland, where two large-scale pilots between 2015 and 2019 involved roughly 2,500 workers, representing more than one percent of the country's working population. The Icelandic trials, which reduced weekly hours from forty to thirty-five or thirty-six, found that productivity remained the same or improved across most workplaces. Following the trials, Icelandic unions negotiated shorter working hours for tens of thousands of workers. Additional national or regional pilots have taken place in Spain, Portugal, Germany, and several other countries.

Critics note that the four-day model works more readily in knowledge-economy roles than in service, manufacturing, or healthcare settings where physical presence is required during fixed hours. Companies in the UK pilot were self-selected and tended to be small to mid-sized firms in professional services, technology, and creative industries. The long-term effects on career progression, compensation structures, and economic output across diverse sectors remain subjects of ongoing research.