A DualBeam instrument is a focused ion beam (FIB) column and a scanning electron microscope (SEM) on the same platform. The synergistic combination of FIB and SEM enables both 2D and 3D characterization of buried interfaces where site specific precision and throughput may be critical. Interphase interfaces as well as internal interfaces (i.e., grain boundaries) often govern material behavior and properties. Direct DualBeam characterization as well as DualBeam specimen preparation for subsequent transmission electron microscopy (TEM) or scanning TEM (STEM) is often the only way to characterize, monitor, or study the failure analysis mechanisms of buried interfaces, especially where nanometer scale devices or material multi-layers exist. Examples of techniques, methods, and applications of DualBeam characterization and specimen preparation of buried interphase interfaces and grain boundaries will be presented.