In order to obtain the least scarring following a surgical procedure, it is crucial that the surgeon always consider the direction of the relaxed skin tension lines involved in the procedure and attempt to obtain a scar that follows that direction as much as possible. No other factor (except the region where the surgery is to be performed) is as important in obtaining an acceptable scar, including the too frequently heralded factor, surgical technique. This article deals with the determination and surgical application of the relaxed skin tension lines.