Ultrasound therapy is an energy-based skin treatment that uses high-frequency sound waves to work within the skin without breaking the surface. In beauty and aesthetic settings it covers a range of devices, from gentler ultrasonic facials that help cleanse, exfoliate and drive skincare ingredients into the skin, through to focused ultrasound systems that heat deeper tissue to encourage the skin to firm and lift over time. The warming effect is designed to stimulate the skin's own collagen, so any tightening tends to build gradually over weeks and months rather than appearing straight away.