Nuclear structure Physics connects to some of our fundamental questions about the creation of universe and its basic constituents. At the same time precise knowledge on the subject has lead to develop many important tools of human kind such as proton therapy radioactive dating etc. This book contains chapters on some of the crucial and trending research topics in nuclear structure including the nuclei lying on the extremes of spin isospin and mass. A better theoretical understanding of these topics is important beyond the confines of the nuclear structure community. Additionally the book will showcase the applicability and success of the different nuclear effective interaction parameters near the drip line where hints for level reordering have already been seen and where one can test the isospin-dependence of the interaction. The book offers comprehensive coverage of the most essential topics including: • Nuclear Structure of Nuclei at or Near Drip-Lines • Synthesis challenges and properties of Superheavy nuclei • Nuclear Structure and Nuclear models - Ab-initio calculations cluster models Shell-model/DSM RMF Skyrme • Shell Closure Magicity and other novel features of nuclei at extremes • Structure of Toroidal Bubble Nuclei halo and other exotic nuclei These topics are not only very interesting from theoretical nuclear physics perspective but are also quite complimentary for ongoing nuclear physics experimental program worldwide. It is hoped that the book chapters written by experienced and well known researchers/experts will be helpful for the master students graduate students and researchers and serve as a standard & uptodate research reference book on the topics covered.