Private equity firms have increasingly acquired physician practices, and particularly dermatology practices. Analyzing commercial claims from the Health Care Cost Institute (2012–17), we used a difference-in-differences design within an event study framework to estimate the prevalence of private equity acquisitions and their impact on dermatologist prices, spending, utilization, and volume of patients. By 2017 one in eleven dermatologists practiced in a private equity–owned practice, and private equity–owned practices employed four advanced practitioners for every ten dermatologists compared with three for non–private equity practices. Private equity firms targeted their acquisitions at larger practices that saw more commercially insured patients compared with practices that were never acquired by private equity firms. The volume of patients per private equity dermatologist ranged from 4.7 percent to 17.0 percent higher than the volume per non–private equity dermatologist up to nine quarters after acquisition. At 1.5 years after acquisition, prices paid to private equity dermatologists for routine medical visits were 3–5 percent higher than those paid to non–private equity dermatologists. There was no significant consistent impact on dermatology spending or use of biopsies, lesion destruction, or Mohs surgery. Policy makers and dermatology practice leaders may want to track the rapidly evolving phenomenon of private equity acquisitions.