This is a report of a symposium focusing on spatially fractionated radiotherapy (SFRT) including GRID, Lattice, Microbeam, as well as ultra-high dose rate irradiation namely FLASH RT. The current status and development of these emerging RT modalities have been summarized in the report. Proton GRID and Lattice published data is limited primarily to a treatment planning and delivery feasibility study. In FLASH at a technological level, electron systems are limited to superficial dose depth profiles; current proton systems have the requisite energy requirements to achieve FLASH dose rates for treating deeper-seated tumors; photon systems remain a challenge, but this may be overcome once systems are designed with higher currents to deliver photons at FLASH dose rates. Following the first clinical trial using transmission proton beams for FLASH, more interests are in utilizing Bragg peak combined with a universal range shifter and beam-specific range compensators to achieve highly conformal FLASH.