In the nearly ten years since the publication of the fifth edition the twenty‐first century continues to be a period of enormous change in the field of occupational health. The importance of reducing the costs of health care have led successive governments to look closely at the need for prevention in respect of work‐related disease, and to consider how occupational health cover might be extended to more workers, especially those in small and medium‐sized enterprises.

A free Fit for Work Service which allowed general practitioners and employers to refer consenting employees to a telephone advice service, staffed by trained occupational health professionals, was withdrawn after only two years because of a paucity of referrals. Amendments have been made to the GP fit note encouraging GPs to recommend adjustments to the workplace and terms and conditions of employment in order to enable employees to return to work despite health conditions. The Health and Safety Executive, which in the past tended to concentrate mainly on workplace accidents, has continued to direct its attention more and more towards health issues. Dame Carol Black’s review of the health of Britain’s working age population (2008), and her later report, co‐authored with David Frost, on sickness absence (2011), raised awareness of the human and economic costs of ill‐health at work. In 2016 a Work, Health, and Disability Green Paper, Improving Lives, initiated consultation on how to halve the disability employment gap. In 2019 Health is Everyone’s Business was published jointly between the Department for Work and Pensions and the Department of Health and Social Care.

There have been many changes in the legal framework, so many that for this edition I have recruited the services of my colleague, Nick Hanning, who has updated Chapter 6 on Civil Liability. I am grateful for his invaluable assistance. The involvement of the European Union continued, especially in the field of health and safety law and laws against discrimination at work, but in 2016 the people of the United Kingdom voted by a small majority to leave the EU. A period of political uncertainty culminated in a General Election in December 2019 which returned a Conservative government led by Boris Johnson to power with an overall majority. At the time of writing the UK has left the EU on 31 January 2020 but subject to a transitional or implementation period until the end of 2020, during which it will continue to be bound by EU law, while an agreement is negotiated governing the future relationship between the UK and the EU Member States. The EU is likely to ask that workers’ rights and environmental standards are protected as part of the bargain but it is impossible at this stage to predict the outcome of the negotiations. It has, however, up to now been generally agreed that when the UK leaves the EU, health and safety and equality laws which stem from EU legislation and decisions of the Court of Justice of the European Union will, for the most part, remain in force. In 2018 the coming into force throughout the EU of the General Data Protection Regulation, and in the UK of a companion Data Protection Act 2018, forced occupational health professionals to undertake a comprehensive review of reporting procedures and the keeping of records. Widespread misunderstanding among some employers and human resources practitioners of the legal and ethical duties of occupational health professionals caused conflict. For that reason, Chapter 3 on Medical Records and Confidentiality has been expanded in this edition. The growth of the use of zero‐hours contracts and the gig economy was examined in 2017 by Matthew Taylor in Good Work: the Taylor Review of Modern Working Practices which made proposals on how employment law might be modified to give greater legal protection to those in insecure employment (Chapter 7).

The law of discrimination at work, in particular disability discrimination, continues to give rise to legal difficulties for occupational health professionals. All the discrimination statutes were consolidated in the Equality Act 2010 – the disability provisions were amended, including a new section 15 which prohibits unfavourable treatment of a disabled person because of something arising in consequence of their disability. There is now voluminous case law on disability discrimination (Chapter 8). The introduction of fees in employment tribunals led to a considerable fall in the number of employment tribunal claims, but the decision of the Supreme Court in 2017, in a case brought by the trade union UNISON, rendering those fees unlawful, has resulted in a substantial restoration of the tribunals’ case load.

I should like to acknowledge the assistance of the late Professor Tim Lee, formerly Professor of Occupational Medicine at the University of Manchester, who first gave me the idea for the book, and his successors, Professor Nicola Cherry and Professor Raymond Agius. Dr Susan Robson, Professor Margot Brazier and Mrs Maureen Mulholland have been towers of strength. Dr John Ballard, Tracy Connors and Marcia Stein of the At Work Partnership have supported me through some difficult times, as have Professor Anne Harriss, Dr Steve Boorman, and Nick Pahl, the Chief Executive of the Society of Occupational Medicine. I have learned a great deal from contributors to the discussion groups of the Association of Local Authority Medical Advisers (ALAMA) and the Higher Education Occupational Practitioners Society (HEOPS), and from many students and participants in training courses. Adelene Chinnick and Carolyn Holleyman have given invaluable assistance in the preparation of the manuscript and I am also grateful to Yogalakshmi Mohanakrishnan from Wiley‐Blackwell.

Although I have retired from my judicial post in the employment tribunal (as well as from my membership of the Industrial Injuries Advisory Council), I continue to practise at the Bar and to be involved in advising and training occupational health professionals in association with Manchester and Cardiff Universities and the At Work Partnership. In 2009 I was elected as the first Chair of the newly created Council for Work and Health; in 2016 the Chairmanship was transferred into the capable hands of Dr Steve Boorman and I was delighted to be elected Honorary President.

It is now nearly 30 years since I gave a copy of the first edition of this book to my husband, Günther Kloss. In the years since his death in 1990 I have been supported by my sons, Peter and Alex, their wives, Allison and Vicky, and my grandchildren, Samantha, Amelia and Jemima. This edition is dedicated to Günther and to all my family.

I have tried to incorporate developments up to December 2019. Where ‘he’, ‘his’, etc. are used, these should be taken to represent both genders.