Crystallography is the experimental Science of determining the structure of materials and the three-dimensional arrangement of Atoms in molecules. This book systematically covers the basics of crystal structure and their organization. All chapters have been amply illustrated to enable ease of understanding of this highly complex subject. To appreciate the use of Crystallography in determining the three-dimensional crystal structure of molecules, shelx programme with relevant plotting routine has been elaborately dealt with. Solved examples and exercises provided would be helpful to the students to have a good understanding of this subject. About the author: Dr. Br>d Velmurugan, Professor, CAs in Crystallography and Biophysics, University of Madras, Chennai, had his graduation and postgraduation from St. Joseph college, Trichy. He did his M.Phil. In the Department of Crystallography and Biophysics, University of Madras, and ph.Br>d under the guidance of the world-renowned statistical crystallographer Prof. S. Parthasarathy from the same Department. He did his post-doctoral research under the Nobel laureate Prof. Herbert a. Hauptman at the medical foundation of buffalo, USA. He has guided 23 ph.Br>d candidates and has published 310 research articles in international publications. He has been awarded the UGC career Award and the Tamil Nadu scientist Award (tansa). he has been a visiting Professor at the Department of Biotechnology and school of engineering, nagoya University, Japan.