Modern Therianthropy is an identity phenomenon categorized by a deep integral or personal belief that an individual is in some way and to some degree, a non-human animal. Physically, Therianthropes are human and understand that they have human bodies.
"Therianthropy is a state of being, whereas someone believes an animal is an essential constituent in their spirituality or life. Therianthropy is an innate part of the person's life. Therianthropy is the recognition and acceptance of the animal within. It makes us what we are, but more importantly who we are.Most Therians identify as earthly animals whether currently living species or extinct species such as dinosaurs. There is not a hard distinction, however, and individuals with mythological or non-earth animal identities may have experiences that are best supported by the Therianthropy community, such as individuals who identify as dragons. Or they may find more support or feel more at home in the Otherkin community.
Because there seems to be some confusion over what a therian is and is not, therianthropy is about the inner nature of one's own self. Therianthropy is about the discovery of the animal within, that we are born with. You cannot become a therian, you must be born that way. While we are not stressing that therianthropy is the only kind of personal animal philosophy/spirituality, we are stressing the differences BETWEEN therianthropy and these other 'ways of life' or spiritual beliefs." 
The majority of Therians are private about their non-human identity and keep more animal-like behavior under control while in public. The ability of Therianthropes to control their actions during shifts, when they feel and act more instinctual and animal-like, is what sets Modern Therianthropy apart from mental disorders such as clinical lycanthropy.
Therians don't know what causes them to identify as non-human. Therianthropy is a subjective belief based on personal experiences and not on scientific fact, with most Therians being "self-labelled" or "self-identified". Therefore, both Spiritual Therianthropy and Psychological Therianthropy are legitimate and acceptable in the community. Their experiences, such as shifting, is essentially the same. The majority within the community agrees that Therianthropy is not a choice. It is subconscious or unconscious.
"Therianthropy is thought by some to be present from birth or acquired in very early childhood because most Therians do not have a memory of ever having not been Therians (though there may have been a period of not recognizing the nature of their Therianthropy)." - Therian Timeline It is also agreed upon that a Therian can not pick and choose a theriotype, the animal which is an individual's identity. Some individuals enjoy the experiences associated with Therianthropy, some do not, and others are indifferent to being a Therianthrope.
Skeptics might argue that identifying as Therian occurred after finding the online community, but Therianthropy is not a group identity. It is a personal identity with the majority of Therians feeling non-human and/or exhibiting species-specific behavior before finding and participating with the online community.* Therians often share memories from childhood of having always experienced a vague feeling of being other than human.
*People without a previous history of therianthropic-like feelings/experiences who do identify as Therian AFTER coming across information about it (commonly on Youtube, Tumblr, Instagram, and Facebook where inaccurate information is shared) are usually met with more skepticism and questioning on more well-known and established forums. They may be suffering from what is known as Shifter's Disease.
- See also: Common Misconceptions
As the online community grew, some people felt the need to coin new terms for different or varying experiences.
The word Therianthropy originates from a portmanteu of the Greek words Therios and Anthropos (animal and human respectively) which, combined, loosely translate to "human animal" or "animal man". It was originally used to describe creatures or men who could change shape and become something else. Werewolves, werecats, and other werecreatures could be described as Therianthropes, though it is a very broad term and it is more acceptable to use their species specific labels.
Therianthropy stretches back to the dark ages, allegedly being used in werewolf trials of the 16th century, and to refer to shapeshifters throughout history. There are currently no documented cases of the term being used to describe similar situations to that of current, modern day Therians, but there are many well documented examples of what could be considered Therianthropy.
Modern day usage of the word is thought to have originated in the early 1990's, when users of the werewolf newsgroup Alt.Horror.Werewolves (or A.H.W.W.) began discussing their spiritual and mental connections with their animals, asserting that they were in fact their therioside.  At first, the term Lycanthrope or Werewolf was most commonly used, but Therianthropy became more widely accepted as it catered to all species, and not just wolves. A.H.W.W. is credited the birthplace of the online Therian community.
- Bricker, Natalei, "Life Stories of Therianthropes: An Analysis of Nonhuman Identity in a Narrative Identity Model" (2016) http://publications.lakeforest.edu/seniortheses/63/
- Grivell et all, "An Interpretative Phenomenological Analysis of Identity in the Therian Community" (2014) http://www.tandfonline.com/doi/full/10.1080/15283488.2014.891999
- ↑ Shifters.org Encyclopedia - http://web.archive.org/web/20060821231231/http://www.therianthropy.org/SO/terms-t.htm
- ↑ Therian Timeline, Mind of the Were, Development - http://theriantimeline.com/therianthropy/the_mind_of_the_were
- ↑ "Foundation's Edge: The History of the Online Werecommunity, Jakkal, 1999. http://web.archive.org/web/20010620111439/http:/www.were.net/foundation.shtml