Prof. Gautam R. Desiraju (born 21 August 1952) is an Indian structural chemist and Honorary Professor at the Indian Institute of Science, Bengaluru. A pioneer of crystal engineering, he helped establish the importance of weak hydrogen bonds and introduced the “supramolecular synthon” concept.He served as President of the International Union of Crystallography (2011–2014). Educated at St. Xavier’s College (University of Bombay) and the University of Illinois at Urbana–Champaign (PhD, 1976), he has authored/edited several influential books: Organic Solid State Chemistry (1987), Crystal Engineering: The Design of Organic Solids (1989), The Crystal as a Supramolecular Entity (1996), The Weak Hydrogen Bond: In Structural Chemistry and Biology (1999, with T. Steiner), Crystal Design: Structure and Function (2003), Crystal Engineering: A Textbook (2011, with J. J. Vittal and A. Ramanan), and the broader-interest book Bhārat: India 2.0 (2022).He remains one of India’s most cited chemists and a leading voice on the future of chemistry and science in the country.His latest book 'Delimitation and States Reorganization: For a Better Democracy in Bharat' is now out.