The Core mission is to provide state-of-the-art light microscopy instrumentation to anyone in the CCR and NIH who requires assistance with fluorescence imaging. Present work in the Core revolves around several established techniques: structural and morphometrical studies based on colocalization of different fluorescent markers by high-resolution and super-resolution techniques, 4D and 5D time-lapse analysis to follow how cellular components change over time and how cellular structures, nanomachines and proteins interact, fluorescence recovery after photobleaching to measure mobility and binding of cell molecules and fluorescence resonance energy transfer to measure molecular interactions in live or fixed specimens. For that the Core is maintaining and upgrading high-end commercial microscopes. Currently the Core maintains wide-field optical sectioning workstations Delta Vision Core and Delta Vision Elite, Carl Zeiss LSM780 confocal microscope, Carl Zeiss SIM/dSTORM Elyra Super-resolution microscope. The Core is adapting Single Molecule Tracking techniques. A Single Molecule Tracking microscope was custom-built for the simultaneous multichannel molecule tracking. The Core is building instrument for Single Molecule FRET. The Core submitted a proposal for custom-building of the state-of-the art multifocus microscope for 4D/5D single molecule tracking, not available commercially. The Core constantly surveys the demands for the state-of-the art technology, tests and arranges demonstrations of the new instruments for OMC users and advertises new microscopy methods that may be useful for specific needs of the current and prospective customers.