From the necessity to obtain large data sets on the statistics of plac
ement of lattice orientation (and phase) in polycrystals, there has em
erged a powerful new form of microscopy. Orientation imaging microscop
y consolidates ordinary views of the morphological aspects of the micr
ostructure with knowledge of the local lattice orientation. Such detai
led information enables the investigator to ask new questions about th
e microstructures of metal and ceramic alloys. The answers can be chal
lenging.