In order to achieve proper functioning of particulate drug delivery systems, it is important to know their basic physicochemical characteristics and material properties. This book provides a comprehensive summary of analytical techniques used to characterize particulate drug systems on the micro- and nanoscale. After an introduction to the analytical tools applied to determine particle size, shape and morphology, the book describes common chemical analysis approaches as well as solid state characterization of such systems. Further sections of the book deal with drug release and permeation studies and the interaction of drug particles with cells, their toxicity and safety issues.