The Benjamin Scale proposed by endocrinologist Harry Benjamin in 1966 uses sexual orientation as one of several factors to distinguish between transvestites, "non-surgical" transsexuals, and "true transsexuals".

The Benjamin scale provides a rational and clinically useful way to understand different forms of transsexualism and to distinguish between how people commonly identify in relation to readyness for surgical and/or hormonal treatment changes.

There are also people who have had sexual reassignment surgery (SRS), but do not meet the definition of a transsexual, while other people do not desire SRS, yet clearly meet Benjamin Scale definition of a "true transsexual", such as Miriam Rivera.