Electromagnetic radiation (EMR) may interfere with the operations of electrical and electronic devices. The effect of an inbound EMR, when interfering with the operation of such devices, is called EM interference (EMI). Shielding the electronic equipment against EMI is a major challenge for equipment manufacturers. EMI may compromise the functionality of the electrical or electronic device mostly by inducing spurious currents in the system and causing malfunction of the equipment. A variety of malfunctions can be observed in devices due to EMI [1]. Strong EMI may even permanently damage the system by burning out one or more of its components. Therefore, significant effort has been invested in developing EMI shielding materials that are applied to electrical and electronic components. The range of commercially available shielding materials is vast, and these materials work on a variety of principles, which are covered in detail in available literature. The present review is narrowly focused on lightweight porous materials used in EMI shielding applications. Any radiation mitigation process works based on the balance between reflection, transmission, and attenuation coefficients. The presence of porosity can change this balance and provide different mechanisms of shielding, which is the focus of this review. Ideally, reflection and transmission should be minimized and attenuation should be maximized in the material to protect nearby structures from the effect of EM waves that are reflected or transmitted