Background: Laser resurfacing has been used for treatment of photoaged facial skin since late 1993. Very few long-term follow-up studies regarding the effectiveness and side effects of this procedure have been reported. Method: Patients who received carbon dioxide laser resurfacing for facial photoaging and wrinkling from Dec 17, 1993, to Nov 30, 1996, were followed up with clinical evaluation and patient questionnaires. Histologic study was also performed in 10 representative patients who had had preoperative biopsies. All treatments were performed by 2 experienced laser surgeons (R. E. F. and M. P. G.). Results: One hundred four patients were examined and interviewed with an average 24-month postoperative follow-up (range 12 to 44 months). We observed high patient satisfaction ratings and significant persistence of wrinkle score improvement. Long-term histologic features confirmed the long-lasting nature of the clinical improvement and demonstrated continuing, progressive improvement in solar elastosis deep in the dermis for an average follow-up period of 2 years. Prolonged use of topical tretinoin (retinoic acid) postoperatively may contribute to continued improvement. The incidence of long-term side effects, including pigmentary changes and scarring, was generally very low and these side effects were usually not noticed by the patients. Conclusion: Improvement from cutaneous laser resurfacing has persisted for an average 24-month postoperative period with a low incidence of side effects. Hypopigmentation is the most common long-term side effect and appears to be related to the degree of pre-existing photodamage as it contrasts with the newly healed undamaged skin. (J Am Acad Dermatol 1999;40:401-11.)