We report the arrival of a new Fabry-Perot interferometer, GHAFAS, which will be mounted at the Nasmyth focus of the 4.2 meter William Herschel Telescope on La Palma in July 2007. Using modern technology, with a spectral resolution of the order R>20000, and with a seeing limited spatial resolution, GHAFAS will provide a new look at the H-alpha-emitting gas over a 7×7 arcmin field in the nearby universe. There is much science which can be done on a 4.2 metre class telescope in world class seeing conditions with a scanning Fabry-Perot. Not only galaxies but HII regions, planetary nebulae, supernova remnants and the diffuse interstellar medium are subjects for which unique data can be acquired rapidly and often in bright time. Our team will inaugurate GHAFAS by studying in detail the dynamics of nearby spiral galaxies. We have developed a robust set of state-of-the-arts tools for analyzing the data cubes delivered by GHAFAS. These tools will also be presented.