Abstract We request funds to purchase a shared light sheet fluorescent microscope (LSFM) that is required for a diverse group of NIH-funded investigators at the University of Alabama at Birmingham (UAB) to advance our abilities to perform High Resolution, large volume imaging of both optically cleared and live samples. This new state-of-the- art microscope will be supported in the UAB High Resolution Imaging Facility (HRIF) - an established microscopy core that will oversee operation, training, and service. LSFM will allow us to image intact tissues, organs, organoids, embryos, and organisms in both fixed and cleared and live preparations. UAB currently lacks a system for high resolution large-volume imaging. LSFM employs a novel configuration that facilitates fast high resolution 3D/4D imaging of intact tissues and organisms without physical sectioning. Considering the scientific needs of our user group, we selected the Zeiss Lightsheet 7 microscope as the best choice to meet our requirements for state-of-the-art live and optically cleared tissue imaging at a range of sample sizes, refractive indices, and resolutions. Eight NIH-funded major users critically require LSFM to advance their research programs. LSFM will provide our research group with several major technical advantages. First, LSFM acquires images at high speeds, and thus data collection from large samples is rapid and efficient, allowing us to image far larger samples than we are currently capable of, including whole organisms and intact cleared tissues. Second, LSFM substantially reduces photobleaching and photodamage. Third, samples do not need to be mounted on a slide/coverslip allowing more physiological imaging of model organisms and intact tissues. Finally, samples can be rotated relative to the imaging plane, allowing ideal orientation and collection of multiple views. The Lightsheet 7 will serve as a synergistic junction for our research group with diverse interests in developmental biology, pulmonology, and neuroscience. The eight major users will utilize the instrument to image live zebrafish, xenopus, organoids, and bone organ cultures, and cleared tissues including lung, brain, mouse embryos, and muscle. The Lightsheet 7 will be located in the established and university-wide HRIF microscopy core, thereby facilitating access by a diverse group of investigators from across UAB. There is strong institutional support for this microscope with substantial contributions from the university and a long-standing commitment to supporting the needs of the core for space, personnel, and administrative services. The PI is an expert in fluorescence microscopy with over 20 years of experience in developing and applying novel techniques to study cell biology and 10 years as a microscopy core director. The requested microscope will be supported day-to-day by a scientist with 5 years of experience working with and training HRIF users with a variety of live and fixed samples in fluorescence...