Notes
This book gives general information. It isn't medical, legal or career advice, and it's no substitute for a professional who knows your situation. NHS and GOV.UK guidance is quoted as I found it in September 2026. The NHS guidance applies to England and the working time rules to Great Britain.
I've kept sources out of the chapters where I could so they read easily. Here they are by chapter, with the limits I'm aware of. Unless I say otherwise, I read the published summary of each paper and not the full text. I checked each paper for a retraction or correction notice in September 2026 and found none on the papers cited. Where a chapter isn't listed, it rests on my own reasoning. That includes chapters 1, 2, 10, 12 to 15 and 18. You, Ellie, Sam, Tom, Helen, Priyanka and every other example are invented for illustration.
Before you start. The advice on when to see a GP about stress, and on 111 and 999, is from the NHS page "Stress". The 48-hour average week and the opt-out are from the GOV.UK page "Maximum weekly working hours". The 11 hours of daily rest and the weekly day off are from the GOV.UK page "Rest breaks at work". Acas is the Advisory, Conciliation and Arbitration Service.
Chapter 3. Pencavel, "The productivity of working hours", Economic Journal 125, 2015, pages 2052 to 2076. I read the full text of the freely available working paper version, IZA Discussion Paper 8129, 2014, and the figures of forty-nine, sixty-three, fifty-six and seventy hours are from there. The workers studied were on piece rates in particular munitions jobs, and the observations are of groups of workers and not individuals. Collewet and Sauermann, "Working hours and productivity", Labour Economics 47, 2017, pages 96 to 106. I read the summary of the working paper version. That the call centre was in the Netherlands is from memory. The view that mental work suffers more than manual work from long hours is mine.
Chapter 4. Williamson and Feyer, "Moderate sleep deprivation produces impairments in cognitive and motor performance equivalent to legally prescribed levels of alcohol intoxication", Occupational and Environmental Medicine 57, 2000, pages 649 to 655. The volunteers were kept awake through the night, which isn't the same as a long working day after a normal night's sleep, so applying it to an evening laptop session is my step. The drink-drive limit in England, Wales and Northern Ireland is 0.08 per cent. It's 0.05 per cent in Scotland and most of Europe. Virtanen, Singh-Manoux, Ferrie, Gimeno, Marmot, Elovainio, Jokela, Vahtera and Kivimäki, "Long working hours and cognitive function: the Whitehall II Study", American Journal of Epidemiology 169, 2009, pages 596 to 605. There were 2,214 participants. Dembe, Erickson, Delbos and Banks, "The impact of overtime and long work hours on occupational injuries and illnesses: new evidence from the United States", Occupational and Environmental Medicine 62, 2005, pages 588 to 597. Extending a finding about injuries to errors at a desk is my inference.
Chapter 5. Parkinson's remark opened an essay in The Economist in 1955. It was satire and I've treated it as such. The day before a holiday is my illustration.
Chapter 6. Reid, "Embracing, passing, revealing, and the ideal worker image: how people navigate expected and experienced professional identities", Organization Science 26, 2015, pages 997 to 1017. The published summary confirms the 115 interviews, the use of performance evaluations, and that how people managed their departure from the expected devotion affected how they were evaluated. The details I give, including the comparison of ratings and the ways people arranged lighter schedules, are from my memory of the paper and of the author's own account of it in the business press. Clark, Michel, Zhdanova, Pui and Baltes, "All work and no play? A meta-analytic examination of the correlates and outcomes of workaholism", Journal of Management 42, 2016, pages 1836 to 1873.
Chapter 7. Munsch, Ridgeway and Williams, "Pluralistic ignorance and the flexibility bias: understanding and mitigating flextime and flexplace bias at work", Work and Occupations 41, 2014, pages 40 to 62. The study concerned requests for flexible hours and home working, and not long hours as such. The effect of senior staff working flexibly held for flexible hours and not for working from home. The picture of five people at their desks is mine.
Chapter 8. Pencavel as above. The committee was the Health of Munition Workers Committee, set up in 1915. Sonnentag, Binnewies and Mojza, "Staying well and engaged when demands are high: the role of psychological detachment", Journal of Applied Psychology 95, 2010, pages 965 to 976.
Chapter 9. Belkin, Becker and Conroy, "The invisible leash: the impact of organizational expectations for email monitoring after-hours on employee resources, well-being, and turnover intentions", Group and Organization Management 45, 2020, pages 709 to 740. It was a survey, so it shows association and not cause.
Chapter 11. Clark and colleagues as above. The summary doesn't report the contrast with work engagement, which I've given from memory of the paper and of related work. Kivimäki and 43 colleagues, "Long working hours and risk of coronary heart disease and stroke: a systematic review and meta-analysis of published and unpublished data for 603,838 individuals", Lancet 386, 2015, pages 1739 to 1746. Pega and colleagues, "Global, regional, and national burdens of ischemic heart disease and stroke attributable to exposure to long working hours for 194 countries, 2000 to 2016", Environment International 154, 2021, article 106595. The estimate was 745,194 deaths. Virtanen, Stansfeld, Fuhrer, Ferrie and Kivimäki, "Overtime work as a predictor of major depressive episode: a 5-year follow-up of the Whitehall II study", PLoS One 7, 2012, article e30719. The odds ratio was 2.43, and the range the authors give for it runs from 1.11 to 5.30, which is wide.
Chapter 13. The pay calculation uses the example's own figures. Fifty-five hours against thirty-seven and a half is a 32 per cent lower hourly rate, and seventeen and a half hours a week over 46 working weeks is about 800 hours, or a little over 21 weeks at the contracted rate.
Chapter 16. Gollwitzer and Sheeran, "Implementation intentions and goal achievement: a meta-analysis of effects and processes", Advances in Experimental Social Psychology 38, 2006, pages 69 to 119. The rule and its parts haven't been tested together, and what chapter 15 says to expect is my expectation and not a finding. The idea of a closing routine at the end of the working day is widely taught, and I haven't traced it to a source.