Some may criticize the “cookbook” approach of these chapters. However, this systematic detailing of where, why, and how much onabotulinumtoxinA to inject is necessary to understand when treating a certain problem in a particular area of the body, and, therefore, this detailing was done intentionally. It is important to note, however, that the face is the only area of the body where the muscles attach directly underneath the skin. Consequently, when these muscles contract, they move the skin of the face (hence the designation “mimetic facial muscles”), producing folds and wrinkles always in a perpendicular orientation to the direction of muscle contraction. Nowhere else in the body are there similar mimetic muscles that contract voluntarily or involuntarily whereby nonverbal communication intentionally or unintentionally is expressed. The reader must never lose sight of the fact that every single individual patient is different and should never be treated in an identical way without justification. These next three chapters strive to provide both the neophyte and experienced physician the rationale for why and how a patient should be treated with a particular amount of onabotulinumtoxinA in one area or another for a distinct, reproducible outcome. By explicitly presenting certain techniques and the reasons for their use, the reader also needs to understand that this is only the author’s perception and interpretation of a given aesthetic problem and his approach to managing the problem, for that patient, who may or may not present again in the future in exactly the same way (see chap. 1). Consequently, when a physician is preparing to treat a patient with onabotulinumtoxinA, it does not matter if the patient is new or one who has been treated before, the physician should approach that patient as if he or she were receiving onabotulinumtoxinA for the first time. The physician must comprehensively evaluate the patient’s current aesthetic problem prior to commencing with the injections of onabotulinumtoxinA and not necessarily rely totally on past treatment dosing. The physician should be flexible and treat the patient’s concerns and specific offending changes that are present at the time. Treat the patient, not the picture.