Beamline 12.3.2 at the Advanced Light Source (ALS) is a newly commissioned beamline dedicated to X-ray microdiffraction. It operates in both monochromatic and polychromatic radiation mode. The facility uses a superconducting bending magnet source to deliver an X-ray spectrum ranging from 5 to 22 keV. The beam is focused down to ∼1 μm size at the sample position using a pair of elliptically bent Kirkpatrick–Baez (KB) mirrors enclosed in a vacuum box. The sample placed on high precision stages can be raster-scanned under the microbeam while a diffraction pattern is taken at each step. The arrays of diffraction patterns are then analyzed to derive distribution maps of phases, strain/stress and/or plastic deformation inside the sample.