This volume comprises select peer—reviewed papers from the Indo—French Workshop on Multifragmentation, Collective Flow, and Sub—Threshold Particle Production in Heavy—Ion Reactions held at the Department of Physics, Panjab University, Chandigarh, India in February, 2019. The contents highlight latest research trends in intermediate energy nuclear physics and emphasize on the various reaction mechanisms which take place in heavy—ion collisions. The chapters contribute to the understanding of interactions that govern the dynamics at sub—nucleonic level. The book includes contributions from global experts hailing from major research facilities of nuclear physics, and provides a good balance between experimental and theoretical model based studies. Given the range of topics covered, this book can be a useful reference for students and researchers interested in the field of heavy—ion reactions.