Sexology is the systematic study of human sexuality. It encompasses all aspects of sexuality (except involuntary celibacy), including attempting to characterise "normal sexuality" and its variants, including paraphilias.
Modern sexology is a multidisciplinary field which uses the techniques of fields including biology, medicine, psychology, statistics, epidemiology, sociology, anthropology, and sometimes criminology to bear on its subject. It studies human sexual development and the development of sexual relationships as well as the mechanics of sexual intercourse and sexual malfunction. It also documents the sexuality of special groups, such as handicapped, children, and elderly, and studies sexual pathologies such as sex addiction and child sexual abuse.
Note that sexology is considered descriptive, not prescriptive: it attempts to document reality, not to prescribe what behavior is suitable, ethical, or moral. Sexology has often been the subject of controversy between supporters of sexology, those who believe that sexology pries into matters held sacrosanct, and those who philosophically object to its claims of objectivity and empiricism.
A number of ancient sex manuals exist, including Ovid's Ars Amatoria, the Kama Sutra of Vatsyayana, the Ananga Ranga and The Perfumed Garden for the Soul's Recreation. However, none of these treated sex as the subject of a formal field of scientific or medical research.
One of the earliest sex researchers prior to the 20th century sexology movement was Richard Freiherr von Krafft-Ebing, whose book Psychopathia Sexualis, published in 1886, recorded a dizzying array of sexual anomalies.
In the late 19th and early 20th centuries, Sigmund Freud developed a theory of sexuality based on his studies of his clients. Wilhelm Reich and Otto Gross, were disciples of Freud, but rejected by him because of their emphasis of the role of sexuality for the revolutionary struggle for the emancipation of mankind.
Magnus Hirschfeld founded the Institut für Sexualwissenschaft (Institute for Sexology) in Berlin in 1919. When the Nazis took power, one of their first actions, on May 6, 1933, was to destroy the Institute and burn the library.
In 1947, Alfred Kinsey founded the Institute for Sex Research at Indiana University at Bloomington, now called the Kinsey Institute for Research in Sex, Gender and Reproduction.
Masters and Johnson released their works Human Sexual Response in 1966 and Human Sexual Inadequacy in 1970. Their books sold well, and they were founders of what became to be known as the Masters & Johnson Institute in 1978.
Fritz Klein MD developed the Klein Sexual Orientation Grid a multi-dimensional system for describing complex sexual orientation, similar to the Kinsey scale, but measuring seven different vectors of sexual orientation and identity separately, and allowing for change over time. In 1978 Klein published The Bisexual Option, a groundbreaking psychological study of bisexuality and in 1998, he founded the American Institute of Bisexuality (AIB) to encourage, support and assist research and education about bisexuality.
The late Vern Bullough was a historian of sexology, as well as a researcher in the field. A list of his books is provided.
Scope of sexology
Sexology, as we currently define it, is largely a 20th and 21st century phenomenon.
Sexology relates to a number of other fields of study:
several fields of medicine, including andrology, gynaecology, and the anatomy of the sex organs the psychology, sociology, and anthropology of sexual behavior neuroscience can be used to study many basic sexual reflexes, and is increasingly relevant to more complex aspects of sexual behavior psychiatry studies disorders of sexual behavior when they impact on clinical conditions or reach a point where they become dysfunctional or sources of psychological difficulty. many aspects of sexual behavior are or have been regulated by law in various jurisdictions, and various classes of sexual offences are studied by criminology biology (general) and ethology (behavioral) study the sexual behavior of other animals, which can be compared with human sexual behavior the techniques of evolutionary biology can be brought to bear on the causes of sexual behavior the epidemiology of sexually transmitted diseases Sexology also touches on public issues such as the debates over abortion, public health, birth control, sexual abuse and reproductive technology.
This is a list of notable sexologists, sorted by the year of their birth:
- Richard Freiherr von Krafft-Ebing (1840–1902)
- Sigmund Freud (1856-1939)
- Wilhelm Fliess (1858-1928)
- Havelock Ellis (1859-1939)
- Albert Moll (1862-1939)
- Edward Westermarck (1862-1939)
- Magnus Hirschfeld (1868-1935)
- Iwan Bloch (1872-1922)
- Theodor Hendrik van de Velde (1873-1937)
- Max Marcuse (1877-1963)
- Otto Gross (1877-1920)
- Ernst Gräfenberg (1881-1957)
- Harry Benjamin (1885-1986)
- Theodor Reik (1888-1969)
- Alfred Kinsey (1894-1956)
- Wilhelm Reich (1897-1957)
- Wardell Pomeroy (1913-2001)
- Albert Ellis (born 1913)
- Kurt Freund (1914-1996)
- Ernest Borneman (1915-1995)
- William Masters (1915-2001) and Virginia Johnson (born 1925) - see Masters and Johnson
- Paul H. Gebhard (born 1917)
- John Money (1921-2006)
- Preben Hertoft (born 1928)
- Oswalt Kolle (born 1928)
- Vern Bullough (1928-2006) 
- William E. Simon (1930-2000)
- John H. Gagnon  (born 1931)
- Fritz Klein (1932–2006)
- Milton Diamond (born 1934)
- Erwin J. Haeberle (born 1936)
- Rolf Gindorf (born 1939)
- Simon LeVay (born 1943)
- Volkmar Sigusch (born 1943)
- Shere Hite (born 1943)
- Anne Fausto-Sterling (born 1944)
- Gilbert Herdt (born 1949)
- Edward O. Laumann