Soft X-ray microscopy can image whole, hydrated, biological specimens up to 10 microns thick with a spatial resolution better than 50 nm [1-4]. Soft X-ray microscopy uses photons with energies between the K shell absorption edges of carbon (284 eV, =4.4 nm) and oxygen (543 eV, =2.3 nm). These photons readily penetrate the aqueous environment while encountering significant absorption from carbon-and nitrogen-containing organic material. In this energy range, referred to as the 'water window,' organic material absorbs approximately an order of magnitude more strongly than water, producing a quantifiable natural contrast and eliminating the need for contrast enhancement procedures to visualize cellular structures.