The programmable array microscope (PAM) is a powerful tool combining the capabilities of nearly all previously described optical sectioning techniques in a single microscope. Not only can the user create optical sections of threedimensional objects, but the PAM's unique adaptive optical strategy allows a user to select the best sectioning method for a particular sample or experimental need. The key to the PAM is a spatial light modulator (SLM). This device, when placed in the image plane of a microscope, can be used to create optical sectioning, generate spatial encoding masks, and/or define regions of interest. The growing family of PAMs includes optical sectioning systems operating in fluorescence4'3'7112 and reflection7'112, as well as spectroscopic imaging systems for fluorescence emission spectroscopy. Perhaps the most common application of this unique family of adaptive optical systems is optical sectioning.