Ultrasound results when electrical energy is converted to sound waves at frequencies above the range of human hearing. These sound waves can then be transferred to tissue. The depth of penetration is dependent on the frequency; the higher the frequency, the less the tissue penetration. Therapeutic ultrasound for the treatment of wounds has been around since the late 1940s. However, more recently, the nonthermal effects of ultrasound are becoming recognized. This type of ultrasound produces two effects: cavitation and streaming. Cavitation is the formation of gas bubbles and streaming is the mechanical force. Many laboratory studies have been done to look at its effects on wound healing. Some of these effects include: collagen synthesis, increased tensile strength, angiogenesis, wound contraction, fibroblast stimulation, and reduction of the inflammatory phase. However, fewer clinical studies have been done. A major medical center performed a case series of 5 patients using ultrasound to mechanically debride their chronic wounds. Patients received a range of one ultrasound treatment up to 5 treatments based on the needs of the individual wound. Quantitative swabs were taken prior to the ultrasound treatment and immediately after the treatment. Results of the case series will be presented.