For some time, the need has been recognized for an X-ray diffraction unit applicable to studies concerning the crystallographic characteristics of pile irradiated materials. Except for studies involving specimens of low activity, it has been impossible in the past to investigate materials which emit intense beta and gamma radiations. The exact type and degree of irradiation damage to high activity materials has been largely a matter of theoretical conjecture. The object of this report is to describe an X-ray diffraction spectrometer that can be used to collect crystallographic data from irradiated materials.