Background: With the baby boomer generation firmly ensconced in middle age and the ubiquity of botulinum toxin type A, nonsurgical facial rejuvenation is becoming increasingly prevalent. As this generation continues to age, products with greater therapeutic power to correct aging changes will be in growing demand. Methods: A multicenter, double-blind, randomized, within-subject, controlled study was conducted comparing Juvéderm Ultra Plus hyaluronic acid filler with bovine collagen. A subset of subjects classified as having treatment for severe nasolabial folds is presented in this article. Subjects received Juvéderm Ultra Plus in one severe nasolabial fold and Zyplast collagen in the other nasolabial fold; up to two touch-up treatments were allowed at 2-week intervals. Nasolabial fold severity was evaluated every 4 weeks for 24 weeks using a five-point scale. Treatment site reactions and adverse events were also recorded. A complimentary treatment was offered at the end of the trial, with effectiveness evaluations just before retreatment and up to 48 weeks after repeated treatment for a subset of subjects. Results: Of the 87 subjects, most were female Caucasians, but all Fitzpatrick skin types were represented (36 percent types IV through VI). At 24 weeks, 96 percent of nasolabial folds treated with Juvéderm had maintained clinically significant correction, and 81 percent maintained the correction for 1 year or more. Results were similar for those subjects with follow-up through 48 weeks after repeated treatment. The median volume required for repeated treatment with Juvéderm was significantly less than that for initial treatment (0.7 ml versus 1.6 ml). Conclusion: Juvéderm Ultra Plus provides correction of severe nasolabial folds through 1 year or more.