This 6-month study evaluated the efficacy and safety of treatment with a nonablative radiofrequency (RF) device.Eighty-six subjects received a single treatment with the ThermaCool TC System (Thermage, Inc., Hayward, CA) and were evaluated for 6 months after treatment.Independent scoring of blinded photographs resulted in Fitzpatrick wrinkle score improvements of at least 1 point in 83.2% (99/119) of treated periorbital areas. Treating physicians, without reference to pre-treatment photographs, noted improvements in 28.9% (48/166) of treatment areas. Fifty percent (41/82) of subjects reported being satisfied or very satisfied with periorbital wrinkle reductions. Objective photographic analysis showed that 61.5% (40/65) of eyebrows were lifted by at least 0.5 mm. Rates and duration of edema/erythema were very low (e.g., vs. ablative procedures). Overall 2nd-degree burn incidence was 0.36% (21 per 5,858 RF applications). Three patients had small areas of residual scarring at 6 months.A single treatment with this RF tissue tightening (RFTT) device produces objective and subjective reductions in periorbital wrinkles, measurable changes in brow position, and acceptable epidermal safety. These changes were indicative of a thermally induced early tissue-tightening effect followed by additional tightening over a time course consistent with a thermal wound healing response.