Thank you for your question mar20. Ultherapy and radiofrequency are both treatments that can be done for skin tightening. Radiofrequency heats up multiple layers of the skin, and usually these are the surface layers. Ultherapy, on the other hand, uses ultrasound to focus energy in the deeper layers of the skin, the same layers that are addressed with a surgical facelift (SMAS). The collagen in the skin is found in many layers and Ultherapy and radiofrequency devices can be combined to stimulate collagen formation in multiple layers. There is no reason that Ultherapy and radiofrequency cannot be done on the same day. This is usually not an issue because most people require only a single Ultherapy treatment but multiple rqdiofrequency treatments (every one to two weeks). Please consult with a doctor for specific recommendations. Good luck!