Summary: Facial soft-tissue augmentation by injection has become increasingly popular as a minimally invasive option for patients seeking cosmetic facial enhancement. Surgical rejuvenation procedures of the face often relate to a less than comprehensive solution to many of the changes that occur with age. Indeed, the surgical lift, while providing the opportunity for soft-tissue repositioning, often fails to provide volumetric restoration to the face that is lost with aging. Appreciating the necessity of replacing depleted soft tissue has allowed for a more comprehensive approach to total facial rejuvenation. Hundreds of filling agents are available worldwide, and the enormity of options has led to confusion about which agents work best, where, and why. The vast array of available soft-tissue filling agents can be distilled into two simple categories: nonpermanent and permanent. In this article, the authors mostly limit their discussion, consistent with the mission of this supplement, to the evolution of nonpermanent filling agents, providing a rationale for their emergence and their individual use.