Sex reassignment surgery is the procedure used to transform one's genitals into those of the opposite sex. The process can be draining on both a person's emotions and wallet, but it's a major step in achieving and maintaining an alternate gender identity. The number of procedures performed in the U.S. is estimated to be between 100 and 500, with the global number perhaps two to five times larger. Male-to-female reassignment surgery is often more successful than its female-to-male counterpart, due to the fact that it is more difficult to create a functioning penis from limited clitoral tissue. MF reassignment involves reshaping the male genitals in the form of a vagina. Sometimes referred to as a vaginoplasty, the surgery entails removal of the testicles and inversion of the penis. Check out the animation below to get a look at exactly how a surgeon accomplishes the transformation. Source