Bisexual orientation is defined as sexual involvement with members of both sexes concurrently (within a one-year period) or any sexual attraction to or involvement with members of both sexes at any time in one's life.

In general, bisexuality is commonly used to represent romantic or sexual feelings toward both men and women. It can be defined narrowly as sexual involvement with members of both sexes concurrently (within a one-year period or less) or defined more broadly as any sexual attraction to or involvement with members of both sexes at any time in one's life. Few people qualify as bisexual in its narrow definition. Though study results vary, some have found that fewer than 1% of males (0.7%) or females (0.3%) engage in sexual activity with both males and females within a one-year period, and as of 2015 there were no established statistics on numbers of Americans who have ever engaged in sex with people of both genders.

Sigmund Freud advanced the idea that bisexuality was a disposition common to all humans. He contended that every individual has a masculine and feminine side and that each side is attracted to members of the opposite sex. Most people, however, repress one side, becoming either hetero-or homosexual. Years after Freud, Alfred Kinsey developed a scale for human sexuality ranging from zero, representing exclusive heterosexual behavior, to six, representing exclusive homosexual behavior. A spectrum of bisexual activity lies between the two poles, a construct that agrees with the definition published in 2013 by the American Psychological Association (APA), which describes bisexuality as falling along a continuum between homosexual and heterosexual. The Klein Sexual Orientation Grid defines sexual orientation using seven different variables over time that address sexual preferences based on attraction, behavior, fantasies, emotional involvement, social involvement, lifestyle, and self-identification. Klein's grid has been simplified by authors Weinberg, Williams, and Pryor in their book Dual Attraction: Understanding Bisexuality, which uses only three variables to define sexual orientation: sexual feelings, sexual activities, and romantic feelings. Besides feelings of attraction, fantasies, and arousal, for example, sexual activities are actual sexual behaviors such as kissing and intercourse. Romantic feelings include the experience of falling in love. Selfidentified bisexuals can be more or less hetero-or homosexual in each of these categories.

Bisexuals are sometimes accused of being homosexuals in disguise. As a result, they often feel confused about their sexuality. Few resources exist to help bisexuals understand themselves. Homosexual support groups may reject them if they reveal their heterosexual sides; heterosexuals may reject them if they reveal their homosexual feelings. Many bisexuals keep their sexuality private, hiding their genderencompassing feelings from others and sometimes even from themselves. Others lead dual lives, expressing their homosexuality with one group of friends and reserving their heterosexuality for a totally separate social circle, even including heterosexual marriage.

For a period of time in the twentieth century, concern over the spread of AIDS resulted in another backlash against bisexuality, based on the assumption that bisexuals may be promiscuous. It may be that most bisexuals are monogamous for all or part of their lives, and those who engage in promiscuous behavior are not necessarily at greater risk of contracting AIDS than others who engage in risky sexual behavior.

Research studies have suggested that high sex drive in women may be associated with increased sexual attraction to both women and men, but that, among men, high sex drive is associated with increased attraction to one sex or the other rather than to both. Also, same-sex and other-sex attraction may be more mutually exclusive among men than among women. These research results suggest that the determination of sexual orientation appears to have a biological component that accounts for differences in patterns of bisexuality, heterosexuality, and homosexuality among men and women.

Life, and love, can become quite complicated for a bisexual person as well as stressful and emotionally painful. Unlike people in other minorities such as ethnic or racial minorities, most bisexual individuals, as well as gay and lesbian individuals, are not raised in communities of others of the same persuasion where they will learn their identity and feel supported. Instead the communities in which they are raised may be judgmental and critical or even outright hostile toward their sexuality. In the early 2000s, however, U.S. society began to shift to greater acceptance and understanding of bisexuality and homosexuality as knowledge and awareness grew through research, activism, and popular media. The American Psychological Association has urged psychologists to help remove the stigma of mental illness that was formerly associated with homosexual and bisexual orientation to avoid the negative psychological effects of prejudice and discrimination.

See also Heterosexuality ; Sexual identity .


Sexually responsive to both sexes.
Sexual attraction to people of the opposite sex, commonly termed straight.
Sexual attraction to people of one's own sex, commonly termed gay.
sexual orientation—
An enduring pattern of emotional, romantic, and/or sexual attraction to men, women, or both sexes, and a sense of identity based on those attractions and related behaviors.



D'Augelli, Anthony R., and Charlotte J. Patterson. Lesbian, Gay, and Bisexual Identities Over the Lifespan: Psychological Perspectives. New York: Oxford University Press, 1995.

Ouhs, Robin, and Sarah E. Rowley. Getting Bi: Voices of Bisexuals Around the World, 2nd ed. Boston: Bisexuality Resource Center, 2009.

Weinberg, Martin S., Colin J. Williams, and Douglas W. Pryor. Dual Attraction: Understanding Bisexuality. New York: Oxford University Press, 1995.


Diamond, Lisa M. “Female Bisexuality from Adolescence to Adulthood: Results from a 10-Year Longitudinal Study.” Developmental Psychology 44, no. 1 (January 2008): 5–179.

Lippa, Richard A. “The Relation Between Sex Drive and Sexual Attration to Men and Women: A CrossNational Study of Heterosexual, Bisexual, and Homosexual Men and Women.” Archives of Sexual Behavior 36, no. 2 (April 2007): 209–22.


American Psychological Association. “Sexual orientation and Homosexuality.” (accessed July 23, 2015).


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