Airport security is a well-known practical topic that we are all familiar with. Laptops, liquids, or even shoes are being inspected while we are traveling. The baggage scanning process is time-consuming and annoying at times, which is required to provide safety for all airplane passengers. There are currently two system approaches that can be used to improve baggage scanning at the checkpoint: energy-discriminating CT technologies and forward scattering X-ray diffraction (XRD). Number of companies have been working for a number of years together on developing suitable detector architectures required by next-generation scanner equipment. This chapter discusses various architectural choices that one needs to make to build efficient CT and XRD systems using direct conversion detectors. To improve material discrimination in baggage scanning, better energy resolution detector materials are required. Cadmium zinc telluride (CZT) is a unique semiconductor that is comparable in performance with germanium (Ge) detectors but, unlike Ge, CZT operates at room temperature. In addition, it outperforms existing energy-integrating scintillation material traditionally used for transmission imaging in terms of spectral resolution while being able to handle comparable count rates. The unique combination of spectroscopy (energy resolution of 2–3 keV) and high-count rate capability (10–1000 Mcps/mm2) at room temperature makes CZT an ideal detector solution for high detection accuracy baggage scanning applications. Some practical examples of CZT-based scanners are shown in this chapter.