The radiation pattern is a critical feature for both an antenna element and an array, and thus an optimization or synthesis process is crucial for the antenna/array design. Such a process can be conducted to achieve e.g. the maximum and null direction, beamwidth reduction, multi-lobe switch for a radiator element, and the beamforming, low side lobe, wide scanning angle for an array with an economic layout. More often than not, the above desired properties are even required for wide band applications, which is a tremendous challenge. This session focuses on the pertinent cutting-edge techniques, including but not limited to parasitic loading, characteristic mode based analysis, and intelligent algorithms, etc.