There are over 1,100 registered (https://ishrs.org/wp-content/uploads/2017/12/report_2017_ishrs_practice_census-08-21-17.pdf) hair transplant doctors in the world as of the 2017. But be WARNED: not all hair transplant doctors are the same!
Some are super dedicated, full time, highly skilled, and highly experienced experts. Others are part time practitioners with no interest in full time hair transplant specialization-possessing only a moderate skill and experience level. And finally, there are those who have virtually no skill or experience and often act outside the law. This latter group has been become such a problem that a movement (https://ishrs.org/bewarehtblackmarket/) to expose it and bring it to the attention of authorities has begun.
To begin your search you will likely type the term "hair transplant" into the google search bar along with your area: ie: "hair transplant" and "Chicago". After hitting enter you will see a bunch of names come up. You will ignore the listings that are paid ads, like everyone does, and begin clicking on the first few clinics in the "organic" section. On each doctor's website you will likely read and see just about the same things: text proclaiming how great and experienced that doctor is, and then a few before/after photos, and then a few testimonials. After looking through three physician websites you will begin to realize you can't really tell the difference between doctors. And it is here that the extra step of using a chat forum comes in.
So, find a hair transplant chat forum, like this one, and simply type the name of each doctor you found in your google search into the search function. See if that doctor posts their results in the forum for the world to see and comment on. If you don't get any hits it may be a red flag- but not necessarily. Perhaps that doctor uses a different forum. So call the clinic and say you are researching that doctor and want to know which chat forums he participates on. If you are told they don't participate on any chat forums, then that is a huge red flag and you may want to drop that doctor from consideration. Why ? Because chat forums give doctors the opportunity to be truly transparent with the public in a way unparalleled in human history.
In the past, patients just had to trust that their doctor was tops in their field. With chat forums this may be confirmed or dismissed very quickly. Just the presence of a doctor on a chat forum is a good sign. Doctors who know they produce substandard work or who simply can't compete don't want anything to do with chat forums. The last thing they want is for the public to know how many procedures they perform per month and what their average patient result looks like.
In a chat forum the public may ask questions that the lower tier doctors will not want to answer. So the solution for them is simply not to join any chat forum at all. And in doing so they send a loud signal out to the public that they don't want to be transparent.
Excellent hair transplant doctors, in sharp contrast, regularly participate on several chat forums. They love to answer questions, are capable of answering even the most detailed question, and regularly post before/after photos and videos of their patient results for the world to see and comment on. Only the most confident and experienced doctors will open themselves up to this level of critique and scrutiny. The rest just don't show up.
So when searching for the best hair transplant doctor, simply find a few chat forums online and see how often they post and how many recent photos and videos they posted. On average a good doctor will have made about 100 postings themselves including about 50 patient results -most of which are recent. Also, read what other patients and members of the public write about that doctor. It can be very illuminating.