This new volume of the highly respected Physics of Thin Films Serial discusses inhomogeneity in real films and surfaces. The volume, guest-edited by K. Vedam, follows the growth of thin films both from the surface of the substrate, and from the atomic level, layer by layer. The text features coverage of Real-Time Spectroscopic Ellipsometry (RTSE) and Reflectance Anisotropy (RA), two major breakthrough optical techniques used to characterize real time and insitu films and surfaces. In six insightful chapters, the contributors assess the impact of these techniques, their strengths and limitations, and their potential for further development.