The Philips CM120 cryo-electron microscope is a computer-controlled transmission instrument dedicated to low dose and cryo-electron microscopic observations. Low electron dose images minimize specimen damage due to electron irradiation, thus enhancing molecular level detail in negative stain and cryo images. Cryo-electron microscopy is a powerful technique applicable to subcellular particles (filaments, viruses, small organelles etc). By avoiding conventional preparative steps (fixation, dehydration, staining), it provides images that are essentially artifact-free, and in some instances with near-atomic level structural detail. The facility possesses plunge-freezing equipment for specimen preparation and a Gatan cryo-holder for specimen observations at temperatures of ~ -185o C. An integral part of the microscope is the computer-controlled goniometer ‘CompuStage’, allowing storage and recall of multiple specimen positions, greatly aiding in cryo-observation. The CM120 is equipped with a TVIPS 2Kx2K CCD camera (F224HD) for direct digital acquisition of images. The TVIPS software allows automated collection of multiple tilt images for electron tomography. A Fischione Advanced Tomography holder allows tilts up to ±80o.