This paper presents a novel approach to three-dimensional (3D) isotropic imaging of living cells using Bessel beam plane illumination microscopy. The authors describe a microscope that combines scanned Bessel beams with structured illumination and/or two-photon excitation to create thin light sheets (<0.5 μm) for 3D subcellular imaging. This method offers 3D isotropic resolution down to ~0.3 μm, speeds up to nearly 200 image planes per second, and allows for noninvasive acquisition of hundreds of 3D data volumes from single living cells. The technique reduces out-of-focus background and photobleaching, enabling extended observations of cellular processes with high volumetric frame rates. The authors demonstrate the effectiveness of the method by imaging various cellular structures and processes in live cells, including mitochondria, filopodia, membrane ruffles, intracellular vesicles, and mitotic chromosomes. The paper also discusses the advantages and potential improvements of the Bessel beam plane illumination microscope, including the possibility of using higher numerical aperture detection objectives and advanced structured illumination algorithms to further enhance resolution and efficiency.This paper presents a novel approach to three-dimensional (3D) isotropic imaging of living cells using Bessel beam plane illumination microscopy. The authors describe a microscope that combines scanned Bessel beams with structured illumination and/or two-photon excitation to create thin light sheets (<0.5 μm) for 3D subcellular imaging. This method offers 3D isotropic resolution down to ~0.3 μm, speeds up to nearly 200 image planes per second, and allows for noninvasive acquisition of hundreds of 3D data volumes from single living cells. The technique reduces out-of-focus background and photobleaching, enabling extended observations of cellular processes with high volumetric frame rates. The authors demonstrate the effectiveness of the method by imaging various cellular structures and processes in live cells, including mitochondria, filopodia, membrane ruffles, intracellular vesicles, and mitotic chromosomes. The paper also discusses the advantages and potential improvements of the Bessel beam plane illumination microscope, including the possibility of using higher numerical aperture detection objectives and advanced structured illumination algorithms to further enhance resolution and efficiency.