A mental disorder or mental illness is a psychological pattern, potentially reflected in behavior, that is generally associated with distress or disability, and which is not considered part of normal development of a person's culture. Mental disorders are generally defined by a combination of how a person feels, acts, thinks or perceives. This may be associated with particular regions or functions of the brain or rest of the nervous system, often in a social context. The recognition and understanding of mental health conditions have changed over time and across cultures and there are still variations in definition, assessment and classification, although standard guideline criteria are widely used. In many cases, there appears to be a continuum between mental health and mental illness, making diagnosis complex. According to the World Health Organisation (WHO), over a third of people in most countries report problems at some time in their life which meet criteria for diagnosis of one or more of the common types of mental disorder.

Elyn Saks is Associate Dean and Orrin B. Evans Professor of Law, Psychology, and Psychiatry and the Behavioral Sciences at the University of Southern California Gould Law School and an expert in mental health law.

She suffers from schizophrenia and has written about her experience with the illness in her autobiography, The Center Cannot Hold: My Journey Through Madness published by Hyperion Books, 2007. Dr. Saks is in training as a psychoanalyst in Southern California.

Saks says "there’s a tremendous need to implode the myths of mental illness, to put a face on it, to show people that a diagnosis does not have to lead to a painful and oblique life". In recent years, researchers have begun talking about mental health care in the same way addiction specialists speak of recovery — the lifelong journey of self-treatment and discipline that guides substance abuse programs. The idea remains controversial: managing a severe mental illness is more complicated than simply avoiding certain behaviors. Approaches include "medication (usually), therapy (often), a measure of good luck (always) — and, most of all, the inner strength to manage one’s demons, if not banish them". That strength can come from any number of places, these former patients say: love, forgiveness, faith in God, a lifelong friendship. Saks says "we who struggle with these disorders can lead full, happy, productive lives, if we have the right resources".

Ruby Wax (born 19 April 1953) is an American comedian who made a career in the United Kingdom as part of the alternative comedy scene in the 1980s.

Wax was born Ruby Wachs, the daughter of Jewish parents who left Austria in 1939 because of the Nazi threat. Her father became wealthy as a sausage manufacturer and her mother qualified as an accountant. Wax was raised in Evanston, Illinois in the 1950s and 60s. Wax elected to major in psychology at the University of California, Berkeley.

Wax came to the UK and studied at the Royal Scottish Academy of Music and Drama. She began her acting career as a straight actress at the Crucible Theatre, Sheffield, where she began a long-standing writing and directing partnership with Alan Rickman, who later was to direct most of her stage comedy shows. In 1978, she joined the Royal Shakespeare Company, working alongside Juliet Stevenson in Measure for Measure, as Jaquenetta opposite Michael Hordern in Love's Labours Lost, replacing Zoë Wanamaker as Jane in The Way of the World and appearing in the Howard Brenton three-hander Sore Throats. While at the RSC, Wax also met and befriended Ian Charleson, and later contributed a chapter to the 1990 book, For Ian Charleson: A Tribute.

Eckhart Tolle (German pronunciation: [ˈɛk.haʁt ˈtʰɔ.lə], English: /ˈɛ.kʰɑrt ˈtʰɒ.lə/; born 1948) is a German-born Canadian resident, best known as the author of the The Power of Now and A New Earth, which were written in English. In 2011, he was listed by the Watkins Review as the most spiritually influential person in the world. In 2008, a New York Times writer called Tolle "the most popular spiritual author in the [United States]."

Tolle says he was depressed for much of his life until he underwent, at age 29, an "inner transformation", then spent several years wandering and unemployed "in a state of deep bliss" before becoming a spiritual teacher. Later, he moved to North America where he began writing his first book, The Power of Now, which was published in 1997 and reached the New York Times Best Seller lists in 2000. Tolle settled in Vancouver, Canada, where he has lived for more than a decade.

The Power of Now and A New Earth sold an estimated three million and five million copies respectively in North America by 2009. In 2008, approximately 35 million people participated in a series of 10 live webinars with Tolle and television talk show presenter Oprah Winfrey. Tolle's books and teachings have stimulated much commentary from theologians and journalists. Tolle is not identified with any particular religion, but his work has been influenced by a wide range of spiritual teachings.

Nikolas Rose (born 1947 in London, UK) is a prominent British sociologist and social theorist. He is currently the Head of Department of the newly launched Department of Social Science, Health & Medicine at King’s College London. He was the James Martin White Professor of Sociology at the London School of Economics, director and founder of LSE's BIOS Centre for the Study of Bioscience, Biomedicine, Biotechnology and Society from 2002-2011.

Before joining LSE in 2002 as the Convenor of the Department of Sociology (2002–2006), he was previously Professor of Sociology at Goldsmiths College, where he had been Head of the Department of Sociology, Pro-Warden for Research and Head of the Goldsmiths Centre for Urban and Community Research and Director of a major evaluation of urban regeneration in South East London.

Originally trained as a biologist, he has done extensive work on the history and sociology of psychiatry, on mental health policy and risk, and on the social implications of recent developments in psychopharmacology. He has also published widely on the genealogy of subjectivity, on the history of empirical thought in sociology, and on changing rationalities of political power. He is particularly known for his interpretation of the work of the French historian and philosopher Michel Foucault and the revival of the literature on governmentality in the Anglo-American world.