characterization of flexible and conformal reconfigurable antennas and the strengths and limitations of available methods are reviewed considering the progress in recent years, and open challenges for future research that are identified. [PERSON] et al. [3] discuss the application of metasurfaces for three different classes of antennas: reconfiguration of surface-wave antenna arrays, realization of high-gain polarization-reconfigurable leaky-wave antennas (LWAs), and performance enhancement of van Atta retrodirective reflectors. The proposed surface-wave antenna is designed by embedding four square ring elements within a metasurface, which improves matching and enhances the gain when compared to conventional square-ring arrays. The design for linear polarization is comprised of a 1 \(\times\) 4 arrangement of ring elements, with a 0.56 \(\lambda\) spacing, placed amidst periodic patches. A 2 \(\times\) 2 arrangement of ring elements is utilized for reconfiguration from linear to circular polarization, where a similar peak gain with better port isolation is realized. A prototype of the 2 \(\times\) 2 array is fabricated and measured; a good agreement is observed between the simulations and the measurements. In addition, the concepts of the design of polarization-diverse holographic metasurface LWAs that form a pencil beam in the desired direction with a reconfigurable polarization are discussed. Recent developments incorporating polarization-reconfigurability in metasurface LWAs are briefly reviewed. In the end, the theory of Van Atta arrays is outlined and their monostatic radar cross-section (RCS) is reviewed. A conventional retrodirective array is designed using aperture-coupled patch antennas with a microstrip-line feeding network, where the scattering from the structure itself degrades the performance of the reflector. This is followed by the integration of judiciously synthesized metasurfaces to reconfigure and improve the performance of retrodirective reflectarrays by removing the abovementioned undesired scattering from the structure. [PERSON] et al. [4] present a new model for radio-frequency switching technology called magnetostatic responsive structure (MRS) that enables reconfigurable operation in 4G/5G antenna frequency bands. Specific frequencies of interest include but are not limited to advanced wireless services (AWS) from 2.18 GHz-2.2 GHz, mid-bands of sub-6 GHz 5G (2.5 GHz and 3.5 GHz), and 4G bands around 600 MHz/700 MHz, 1.7 GHz/2.1 GHz/2.3 GHz/2.5 GHz. The ABCD matrices of the MRS switch are derived from the S-parameter values and are shown to be a good model from 100 kHz to 3.5 GHz. Agreement between simulations, analytical results, and circuit model values is shown. [PERSON] et al. [5] present a robust pin-diode based reconfigurable antenna for WLAN/WiMAX applications. A super-shape elliptical radiator is used to achieve wider intrinsic bandwidth compared to the classical rectangular patch antenna, while the dimensions remain comparable. The proposed antenna is fed at two points, exciting both horizontal and vertical polarization but in different operating frequencies. To achieve wider bandwidth, as a whole but also for each polarization, the symmetrical feeding points for each excitation are also employed with a proper feeding network. PIN diodes are also used in the feeding network to provide the option of narrower bandwidth. A compact reconfigurable UWB MIMO antenna with four radiators that accomplish on-demand band rejection from 4.9 to 6.3 GHz is presented by [PERSON] et al. in [6]. Two radiators are then placed perpendicular to each other to exploit the polarization diversity, leading to high miniaturization. Two additional radiators are then fixed obliquely on the same laminate (without increasing its total size) in an angular configuration at a \(\pm\)45\({}^{\circ}\) angle to the first two planar radiators to further exploit polarization diversity. The design is validated by measurements of a fabricated prototype.