This issue of Macromolecular Symposia contains the papers presented at the 15th European Symposium on Polymer Spectroscopy (ESOPS 15) held in Hersonissos, Greece in June 2003. Recent advances in the applications of a variety of spectroscopic techniques such as infrared, Raman, fluorescence, NMR, mass spectroscopy, electrical and mechanical spectroscopy to the characterization and analysis of polymers systems were demonstrated. In particular, applications of the above techniques to the analysis of polymeric nanocomposites, all-polymer solar cells, biopolymers and food packaging polymers as well as theoretical and fundamental aspects in polymer spectroscopy are the topics covered in this volume.