We cannot hope to understand what we cannot measure and if we cannot understand it we cannot progress. Particle properties can significantly influence the behavior of particle assembles, the quality of products and the efficiency of manufacturing processes. Particle characterization is therefore essential in many industrial processes and for the development of new innovative technologies. In this area our objective is to present state of the art research on particle and bulk powder characterization techniques and applications. Within this space measurements of individual particles, their interactions, and the bulk material behavior will be discussed.