The Merriam-Webster Online Dictionary defines discrimination as "the act, practice, or an instance of discriminating categorically rather than individually." In other words, discrimination occurs when an entity (individuals, groups, companies, etc.) actively or passively denies benefits, rights, jobs, and/or opportunities to a person or group of people based on a trait or characteristic not associated with one specific individual. Discrimination has been known to have occurred against groups of people based on race, religion, nationality, ethnicity, gender, and weight.

Discrimination based on sexual orientation has recently gained prominence in the national arena across a variety of professions, organizations, and services. Chapter 10 section 654 of the United States Code states, " (14) The armed forces must maintain personnel policies that exclude persons whose presence in the armed forces would create an unacceptable risk to the armed forces' high standards of morale, good order and discipline, and unit cohesion that are the essence of military capability. (15) The presence in the armed forces of persons who demonstrate a propensity or intent to engage in homosexual acts would create an unacceptable risk to the high standards of morale, good order and discipline, and unit cohesion that are the essence of military capability."

Contrast the above with a statement from the American Library Association in support of diversity based on sexual orientation: " But diversity applies to more than race and ethnicity. It applies to physical disabilities, sexual orientation, age, language and social class. Democracy is rooted in respect for all people. Respect is based on understanding. Librarians believe that education is key to building communities and a nation based on understanding and respect."

Then consider the following resolution made by the Boy Scouts of America: "WHEREAS the national officers further agree that homosexual conduct is inconsistent with the traditional values espoused in the Scout Oath and Law and that an avowed homosexual cannot serve as a role model for the values of the Oath and Law." This resolution was made in the wake of a highly contentious U.S. Supreme Court case in which a former member of the Boy Scouts brought charges of discrimination based on his sexual orientation against the organization. The Supreme Court ruled in favor of the Boy Scouts in a 5-4 vote, thus affirming the right for private organizations to discriminate as they see fit.

Finally, consider this statement from the U.S. Equal Employment Opportunity Comission: "The U.S. Equal Employment Opportunity Commission (EEOC) does not enforce the protections that prohibit discrimination and harassment based on sexual orientation, status as a parent, marital status and political affiliation. However, other federal agencies and many states and municipalities do. The relevant federal agencies are listed below. For assistance in locating your state or local agency, contact the EEOC office nearest you." Reading further on, it becomes apparent that there is an understanding that civil servants will not be discriminated against based on their sexual orientation, but this ONLY applies to this class of workers.

Discrimination against people based on sexual orientation can take any number of forms. Some companies do not provide health benefits for same-gender partners of employees. Other companies in places without legal protections for LGBT workers can legally fire employees for not being heterosexual. Other companies and organizations may practice this type of discrimination in more subversive ways. Homophobic higher-ups may pass over homosexual employees for promotions, or they may "forget" to invite such workers to gatherings and parties (staff parties, holiday parties). Tickets to the company box at the local stadium may be harder to come by for homosexual employees, and such employees may be more likely to be denied merit-based bonuses if the person making those decisions is homophobic. Discrimination based on sexual orientation can vary greatly.