For more than 15 years, the excimer laser has been used as a surgical instrument on the cornea. Photorefractive keratectomy (PRK) followed radial keratotomy as researchers sought a more precise technique. In PRK, precision turned out to depend on surgical technique as well as the wound-healing process, with the 2 factors interdependent. The PRK technique has evolved toward a large diameter, flat ablation curvatures, and an even surface. The role of such factors as cytokines and interleukins has become more clear in the past 10 years. However, understanding the wound-healing process becomes more complicated with increasing know edge. Learning the contributing factors and performing trials with new drugs and antibodies to modulate wound healing have shown positive results on the experimental level. Patient selection based on the concentration of epidermal growth factor in tears may be another way to increase PRK s precision. The PRK technique has taught much about wound healing. For the technique to be competitive, increased precision, particularly in eyes with high myopia, is needed. Two other factors are imperative: controlling postoperative pain and decreasing visual rehabilitation time.