It has been shown that both optical and acoustic signals can be transmitted through clothing. This means that, in
principle, both types of signal could be used for personal screening. In this paper, a description of how each of these
signals interacts with clothing, and the information that can be obtained, will be presented. The wavelengths are very
different - by three orders of magnitude. In fact, the wavelength of ultrasound is of a similar order of magnitude to that used by THz systems (≤ 1 mm), whereas the optical signals that could be used are typically in the micron or so range. This means that their use for screening relies on totally different mechanisms. In this paper, results will be shown for both types of measurements, where the location of hidden objects can be demonstrated. The imaging resolution that can be obtained will be described, together with a discussion of how both types of energy could be used for improved identification of objects hidden beneath layers of clothing.