The iTEM Diffraction extension software released by Soft Imaging System Corp. enables automatic indexing, evaluation, measurement and analysis of diffraction patterns. It is fully integrated with iTEM, the company's transmission electron microscopy (TEM) image analysis system. Diffraction patterns of single- and polycrystalline samples can be indexed. After the crystal structure and lattice parameters have been defined, indexing is performed automatically via threshold detection or manually via definition of the two g-vectors. The TEM method of investigation allows very small sample areas and fine-grain structures to be examined, and high-resolution images of the same sample area can be generated.