European Laboratory for Non-linear Spectroscop 1 article published in JoVE Neuroscience Micron-scale Resolution Optical Tomography of Entire Mouse Brains with Confocal Light Sheet Microscopy Ludovico Silvestri1, Alessandro Bria2,3, Irene Costantini1, Leonardo Sacconi1,4, Hanchuan Peng5, Giulio Iannello2, Francesco Saverio Pavone1,4,6,7 1European Laboratory for Non-linear Spectroscopy (LENS), 2Integrated Research Centre, University Campus Bio-medico of Rome, 3DAEMI, University of Cassino, 4National Institute of Optics (CNR-INO), 5Allen Institute for Brain Science, 6Department of Physics, University of Florence, 7ICON Foundation, Sesto Fiorentino, Italy In this article we describe the full experimental procedure to reconstruct, with high resolution, the fine brain anatomy of fluorescently labeled mouse brains. The described protocol includes sample preparation and clearing, specimen mounting for imaging, data post-processing and multi-scale visualization.