At the heart of being transsexual is the absolute certainty of being trapped in the wrong body, the wrong physical sex, and the wrong definition within the world. The transsexual seeks to correct a flaw of birth, to become a preferred expression of gender. Tied into this basic, biological drive, is the way in which a society accepts and permits gender to be expressed.

While most human societies have universal concepts of gender expression, there are also unique cultural expectations and taboos that themselves alter over time. To enjoy a life accepted and embraced by other human beings, every person must to some degree compromise or alter their natural behavior or desires to fit a common cultural agreement.

People who refuse, or who cannot meet the minimum expectations and requirements of their culture increasingly are rejected by it, to the point of total exclusion, or even violence and annihilation.

Existing within any society is a balancing act between the individual and the expectations of the culture. This becomes a very severe matter when fundamental cultural taboos and requirements are involved.

There is probably no more fundamental cultural definition than that of gender expression.

To be outside the boundaries of sanctioned gender expression is to threaten, at a basic level, the established comfortability and security of a culture. The more rigid the culture, the more profound this effect.

In modern, Euro-Christian post industrial society, rigidity with regard to gender taboos is fairly severe.

The transsexual, in quest to achieve agreement between brain and body, must also cope with a vast array of expectations and taboos that affect every aspect of life, every moment of action, and every nuance of appearance. To succeed without facing a lifelong burden of exclusion, the transsexual must somehow come to terms with both biology, and society.

A transsexual is raised as a gender opposite to their inner gender. The cultural training, and reinforcement of gender specific behaviors, confuses and torments them. By the time they have the opportunity to change their physical sex to agree with their true gender, they are faced with a triple cultural problem. The transsexual must not only unlearn a lifetime of enforced gender role behavior, make up almost overnight for the loss of a lifetime of gender role training culturally appropriate to their true inner gender, but must also find a way to comfortably express their unique personality honestly through that new gender role.

This enormous requirement is only half of the entire path to success, for there is also the matter of physical appearance.

Within human society, the gender definition that other people create when faced with a person, is determined by essentially two things. One is the sum total of behavior, motion, action and emotional presence of the person. The other is the physical appearance, the shape, look, sound, even the smell of the person. In effect, an equation is performed that totals the many factors, and a result, male, female, both, or neither results.

In every way, it is safer, easier, and less filled with suffering to fit neatly within one of the twin accepted poles of the current definition of gender: male or female.

To accomplish this is a complex undertaking. This is "Passing".

Hormones can take care of all, some, or little of the physical side of gender presentation, depending on age and receptivity. Almost all human beings can accept, and be altered by, both male and female hormones. Only a very rare number of humans are insensitive to the effect of applied hormones, and if those rare individuals happen to be transsexual, the soul is in a very difficult position indeed.

The effect of hormones varies somewhat from person to person, and also is dependent on age. The younger a person is, the more quickly, and effectively will be the result of taking hormones. By age 18, the effectiveness of hormone treatment begins to plummet. By age 25, hormone sensitivity is half what it is at 18, by age 30 it levels off at one fourth. This level of sensitivity is maintained for the remainder of life.

Physical passability is fundamentally based on the effectiveness of hormone therapy. No surgery, or other treatment, can replace this most basic foundation of physical sex. Clearly, to be accepted as the correct sex, early hormone therapy is without question the single greatest factor in achieving passability.

Advanced age provides a benefit different from youth, but just as valuable. Advanced age renders both males and females increasingly similar in appearance, as physical sex cues wither and fade, as skin wrinkles and the flesh degrades. This degradation of aging, masks obvious physical differences between the sexes, and thus aids passability.

The very few physical aspects of sex differentiation that hormones cannot change, such as the voice in Male-To-Female transsexuals, and the developed genitals of either sex, must be addressed by other means.

Social passability is a complex mix of natural behaviors and learned affectations.

Worldwide cultural definitions of gender expression have a surprisingly high degree of commonality. How a man is fundamentally expected to act and behave versus how a woman is expected to act and behave is essentially consistent amongst all populations of human beings, regardless of the degree of isolation. We know that gender is hardwired into the brain. It would be irrational to fail to recognize that much of the cultural definitions of gender expression are the result of averaging inborn gender behaviors into a basic human stereotype. However, many arbitrary behavioral expectations and roles are often tacked onto this basic observation. These additional rules change with time, technology, and location.

In order to pass effectively, providing that the physical side is granted,
the transsexual must study and incorporate selected behaviors and conditioning to complete gender presentation. Each transsexual must choose for themselves which of the cultural sex role components they can either live with, or find natural for themselves to express.

A common trap is adhering too strongly to cultural stereotypes, which generally works against passability. To pass successfully, the best tactic is to express the honest self. Since much of cultural sex roles are based on observation of real gender linked behaviors, finding an internal and natural self expression will accomplish as much, or more, than learning an affected role. It is often more successful, precisely because it is not a role, but an honest form of presence in the world.

In a nutshell:

"Passing" increases survivability and overall happiness for the transsexual. Passing is composed of a physical side and a behavioral side. Earliest possible use of hormones is the best guarantee of physical passability. Unlearning sex roles and expressing natural, inborn gender behavior is the most important part of successful behavioral passing.