I have read a ton of posts on the hapkido and tae kwon do forums. I am studying both. My father is a very active instructor and I have grown up around these two Korean Martial Arts. So this is just based on opinions gathered through practice and observation. Hapkido: Founded by Choi. This art in and of itself, as based on the Moo Sul Kwan cirriculum is an all encompassing martial art. You have a plethra of wrist and clothes technique to draw from. Next you have the art of throwing, this is done differently than judo in the application of the throw. The throw does not change, just the set up will be different. Hapkido cirriculum also dictates doing 10 throws with one arm. 25 modifieds, these are throws done from various entries that are done as wrist throws etc. Judo randori is a big teaching aspect. Sparring, jump kicking, spinning kicks and flying kicks are heavily previlant in the cirriculum. Finished off by knife defense, cane techniques. Punching and blocking is very important as well. Now, I am sorry but a kick is a kick. I always kick the same in tae kwon do class as I have learned in hapkido. I have not been scolded for it yet. The main three stances in hapkido, per Moo Sul Kwan: Horse, Sparring, and Front. Tae Kwon Do: One of the best kicking arts, period. Tae Kwon Do, to the Koreans is no different than baseball in America. Tae Kwon Do has many different styles of striking and stances that are used in poomse. In hapkido the knife and ridge hand strikes are taught and practiced. However, there are no forms in gup ranks in hapkido. In Tae Kwon Do poomse is a big part of the cirriculum. Tae Kwon Do incorporates set pf basic techniques which is nothing more than striking, punching and kicking done in combination. One step sparring and of course poomse. Tae Kwon Do is known for its kicking. Sparring, jump kicking, spinning kicks and flying kicks are the cirriculum. Tae Kwon Do has "self-defense" techniques. They are, and let me be real clear on this.....They are not hapkido techniques. Just because two korean arts share the same strikes, kicks, blocks, and stances does not make them similiar arts. They are two different arts with two totally different cirriculums, serving two different purposes.