Instrument D19 at the Insritut Laue Langevin (ILL) is the best high-resolution monochromatic neutron diffractometer in the world. Although it is a well-proven and reliable instrument, major changes in area detector technology since D19 was built (1985) mean that very large gains are nowpossible. Hugely improved performance in terms of speed, accuracy and sample range can be delivered by replacing the current detector system with a state-of-the-art large area detector. Such a development has been recognised throughout the user community as long overdue. A major proposal toupgrade D19 in this way has just been funded by the UK Engineering and Physical Sciences ResearchCouncils (EPSRC). The new detector will produce a gain of -25 in solid angle, and will result in the creation of a fast monochromatic instrument for high-resolution neutron crystallography and neurron fiber diffraction. The will provide exciting opportunities in chemistry, physics and biolo-gy, as well as the obvious gains in terms of dara qualiry, experiment throughput, and cost effective use of valuable neutron beam time. It will be possible to study smaller samples, samples with much larger unit cells, multiple pressure or multiple temperature experiments, and fiber diffraction experiments involving continuous diffraction. As a high resolution monochromatic instrument, well matched for relatively large unit cells, the new D19 will strongly complement the scope of existing ILL instrumentation for small and large molecule crystallography.