AbstractThe Vancouver scar scale, the Manchester scar scale, and the Patient and Observer Scar Assessment Scale (POSAS) are all very well-known scar evaluation methods. These tools are based on a number of scar variables, including color, height, and pliability. However, since all were mainly developed to evaluate burn scars, they are difficult to use in clinical practice for keloids and hypertrophic scars. This is because these pathological scars require both differential diagnosis and a way to evaluate their response to therapy. The Japan Scar Workshop (JSW) has sought to develop a scar assessment scale that meets these clinical needs. The first version of this scar assessment tool was named the JSW scar scale (JSS), and it was reported in 2011. In 2015, the revised second version was reported. The JSS consists of two tables. One is a scar classification table that is used to determine whether the scar is a normal mature scar, a hypertrophic scar, or a keloid. This grading system helps the user to select the most appropriate treatment method for the scar. The other table in the JSS is an evaluation table that is used to judge the response to treatment and for follow-up. Both tables contain sample images of each subjective keloid/hypertrophic scar item that allow the user to evaluate each item without hesitation.