Although Helium Ion Microscopy (HIM) was introduced only a few years ago, many new application fields are budding. The connecting factor between these novel applications is the unique interaction of the primary helium ion beam with the sample material at and just below its surface. In particular, the HIM secondary electron (SE) signal stems from an area that is very well localized around the point of incidence of the primary beam. This makes the HIM well-suited for both high-resolution imaging as well as high resolution nanofabrication. Another advantage in nanofabrication is the low ion backscattering fraction, leading to a weak proximity effect. The lack of a quantitative materials analysis mode (like EDX in Scanning Electron Microscopy, SEM) and a relatively low beam current as compared to the SEM and the Gallium Focused Ion Beam are the present drawbacks of the HIM.