Discoveries In Astronomy And Astrophysics Have Brought Out Several Outstanding Problems And Puzzles. For Resolving These New Inputs From Physics May Be Required. There Exist Several Centers With Excellent Instruments And Many New Instruments Will Be Developed In The Next Few Years. Similarly Several Satellites Are In Orbit And More Are Being Planned For Future Astronomical Studies. Clearly Astronomy And Astrophysics Will Provide Great Opportunities For An Inquisitive Mind To Do First Rate Research Work.There Is A Good Scope For Carrying Out Path Breaking Work In Astronomy, Astrophysics And Space Sciences. To Attract Students And Researchers To This Exciting Frontier, It Is Necessary To Provide Them A Strong Academic Foundation. Astrophysics: A Modern Perspective Is An Attempt In This Direction. This Book Has Evolved Out Of A Series Of Lectures Delivered At Two Winter Schools In Astronomy And Astrophysics Organized By The Tata Institute Of Fundamental Research (Tifr), Bombay. Special Effort Has Been Made To Highlight Some Of The Challenging And Unsolved Problems From The Observational And Theoretical Points Of View.All The Contributors To This Volume Are Well Known Scientists Of Tifr And Have Made Significant And Lasting Contributions In Their Respective Fields. Each Chapter Develops The Subject From Basic Considerations Of Physics And Goes On To The Present Day Understanding. Some Of The Important Problems Facing Astronomers And Astrophysicists Today Are Highlighted Throughout The Book. The Close Interaction Between Astronomers, Astrophysicists And Physicists Has Also Been Brought Out. It Is Hoped That This Approach Will Attract More Students And Research Workers To The Fascinating Area Of Astronomy And Astrophysics.