The Submillimeter and Far-InfraRed Experiment (SAFIRE) on the SOFIA airborne observatory is an imaging Fabry-Perot spectrometer operating at wavelengths between 100 mum and 700 mum. SAFIRE's key science goal is to investigate line emission in galaxies at wavelengths not visible from the ground, and to map the variation in this line emission in nearby galaxies. SOFIA will fly at an altitude where the atmosphere is mostly transparent, permitting SAFIRE to achieve a high point source sensitivity at most wavelengths. With a field of view of 160"x320" at a spectral resolution of similar to200km/s, when SARRE achieved first light in 2006, it will add substantial capability to the first light instrument complement of SOFIA. SAFIRE's top priority observations will be to measure emission lines in the Galactic center, to map emission lines in nearby galaxies, and to understand the physics of the cores of ultraluminous galaxies from the local region to the high redshift universe through far-infrared fine-structure line emission.