The book concerns with the theory and practice of remote radio sensing applied to detection and classification problems with (polarimetric) radar in microwave scattering propagation channel. The first eight (8) chapters (Part II of the book) deal with theory on remote sensing for classification by (polarimetric) contrast of earth-based radar objects. Part III of the book (chapters 9-14) deals with signal processing aspects of (polarimetric) remote sensing for data obtained from experiments carried out at L and X bands. Theory and experiments are compared and an overview of new areas of research on modeling and verification of detection /classification of radar objects are given in Chapters 15 and 16. In Chapter 17 some experimental results of IRCTR radar polarimetry for atmospheric and earth surface applications are given. Part IV gives the conclusions on applications and the results of the research program described in this book.