Scar tissue is an inevitable product of the body’s trauma repair process. In a broad sense, without scar tissue there would be no healing of trauma. However, when scar growth exceeds a certain limit, various complications will occur, such as disruption of appearance and functional mobility. The most common clinical scars occur on skin tissues, but in fact any deep tissues and organs can produce various degrees of scar tissue and possible complications during the repair and healing process of trauma. All trauma treated properly (including techniques such as aseptic technique, debridement, incision and suturing, or tissue grafting) may produce minimal scarring and may avoid functional impairment. If the trauma has not been treated more optimally, significant scarring and functional impairment can occur. If the trauma is followed by a severe infection, scar tissue is bound to increase, leading to more severe disruption of appearance and functional impairment. Another example is the scars caused by deep skin burns (deep II° and III°), which are often accompanied by various degrees of contracture and deformity, which is the most common kind of scars in clinical practice. Plastic surgeons should not only master the techniques of handling various scar tissues, but also actively study how to prevent excessive scars and reduce the functional impairment caused by them. The prevention of scars. On the one hand, the repair of trauma and on the other hand, the formation of scars and the disruption of shape and dysfunction they cause, are two sides of the same coin. “The movement of anything takes place in two states, the state of relative rest and the state of significant change. Both states of motion are caused by the struggle of two contradictory factors contained within the thing against each other.” In clinical practice; many facts illustrate the above universal truth. When we follow some basic principles strictly in the management of wounds, the healing of wounds will produce the least amount of scar tissue. Aseptic technique is one of the most important aspects of this. Often wounds heal quickly and produce minimal scarring only under sterile conditions. In addition, the incision must be sutured without tension to obtain a good result; otherwise, even if the incision heals successfully, it will still gradually produce wide and thickened scar tissue later. The direction of incision is also closely related to the generation of scars. If the incision is made in the direction of the skin grain, there will be less scarring and less dysfunction after healing; if the incision is made in the wrong direction of the skin grain, there will be significant scars and varying degrees of contracture and dysfunction later. In addition, if care is taken to avoid unnecessary surgical trauma, thorough hemostasis, application of fine instruments and materials, and early removal of sutures in the treatment of any trauma, scar tissue is often produced less frequently after the trauma heals. When dealing with deep burns, if the trauma can be properly treated, infection can be prevented or effectively controlled, early healing of the trauma can be promoted, and skin grafting on Ⅲ° burn trauma can be carried out as early as possible, the scar generation and deformity prevention may also be reduced to a great extent. However, on the other hand, certain intrinsic factors of the body, as well as the location of the trauma, are also associated with the development of scars. The tendency for scars to occur in people with darker skin is related to the skin’s excess pigmentation, texture, and oiliness. Scars often begin in women after a small boil near the midline of the chest has healed, which is associated with the constant strain of breast and breathing movements. Another example is the scarring of incisions after thoracic and abdominal surgery which may also be associated with respiratory movements and constant tension on the abdominal wall. It is a metaphysical argument to easily attribute any excessive scarring to so-called “scarring”.