Dermatology is huge in some areas, and not as popular in others. If you look at statistics and the # of dermatologists, given places are much more attractive for practicing skin care professionals to practice. The reason for this is because skin care professionals are practicing skin care professionals, and often deal with beauty issues and difficulties that often face citizens.
The City of Angels. A model town of entertainment in a variety of forms, being beautiful is not much more important anywhere else as it is in the city of Angels. Dermatologists flock here because people are frequently trying to becoming better looking to get their name out in the entertainment world, whether it is movies, television, or modeling. This also filters off onto other areas of life where business experts and elsewhere feel the need to look great as they see other people looking great around them.
New York. NY is the fashion capital of the U.S and because of it, it becomes the other source for dermatology in the US. Being stunning there is arguably more big than Los Angeles, because modeling and fashion puts beauty as a necessity, while television and the big screen only strongly nudge towards it. There is also a decent entertainment industry, although not comparable to the city of angels, where growing stars are doing whatever they can to get an edge up.
These 2 cities are the important points for skin care in the United States, but there are skin care professionals all over the place. Beauty is not the only detail skin care professionals assist with, as they can also deal with skin problems that have nothing to do with looks.