Stimulated Emission Depletion (STED) Microscopy is a super-resolution strategy that is based upon a standard confocal laser scanning microscope. Through the use of a second laser that prevents fluorophore emission outside of a spot smaller than the diffraction limit images can be generated with an approximately three-fold gain in resolution. However, this greatly increases the time required to scan a full field and can also require very high laser powers. Furthermore, care must be taken to not employ fluorophores that would be excited by the depletion laser. 3D, multi-color and live-cell STED have all been realized, and STED is particularly good for imaging within thicker samples.