This book combines the proceedings of Symposium GG, Electron Crystallography for Materials Research, and Symposium HH, Quantitative Characterization of Nanostructured Materials, both from the 2009 MRS Spring Meeting in San Francisco. Papers from Symposium GG focus on the fundamentals and recent progress in electron crystallography and associated strategies for structural fingerprinting of nanocrystals. Some consensus was reached regarding precession electron diffraction and electron diffraction tomography as instrumental breakthroughs leading to ab initio determinations of unknowns with high structural complexity. Some of these unknowns may only exist as nanocrystals. For Symposium HH, experts in a wide variety of probing techniques come together in an effort to find optimal, and often combined, approaches for determining atomic structure at the nanoscale - the problem at the core of nanotechnology.