The Gemini Infrared Multi-Object Spectrograph (GIRMOS) is a powerful new instrument being designed for the Gemini telescope that takes advantage of the latest developments in adaptive optics (AO) and integral field spectrographs. GIRMOS will carry out simultaneous high-angular-resolution, spatially resolved, infrared (1-2.4 µm) spectroscopy of four objects (each 3”x3”) within a two-arcminute field of regard by taking advantage of GeMS and multi-object AO (MOAO). This capability does not currently exist anywhere in the world and offers significant gains over a very broad range of scientific topics in astronomical research. For example, current scientific programs for high redshift galaxies are pushing the limits of what is possible with infrared spectroscopy at 8-10-meter class facilities by requiring several hours of observing time per target. Multiplexing several objects simultaneously with MOAO is absolutely necessary to make effective use of telescope time and obtain statistically significant samples for high redshift science. With an expected commissioning date of 2023, GIRMOS’s capabilities will also make it a key follow-up instrument for the James Webb Space Telescope when it is launched next year, as well as a true scientific and technical pathfinder for future Thirty Meter Telescope (TMT) multi-object integral field spectroscopic instrumentation.