Proceedings of the Baroda Workshop on Nanomaterials, Magnetic Ions and Magnetic Semiconductors studied mostly by Hyperfine Interactions (IWNMS 2004), held in Baroda, India, 10-14 February, 2004. Researchers and graduate students interested in the application of hyperfine interaction techniques, mostly Mössbauer Effect and Perturbed Angular Correlations, to the fast developing fields of magnetic nanomaterials, magnetic ions and magnetic semiconductors will find this volume indispensable. The volume also addresses to the application of synchrotron radiation and ion beams to these systems.