Subrahmanyan Chandrasekhar, Nobel Laureate in Physics, was a towering figure in 20th century physics, but remained a highly private man. The many letters and correspondence in this book reveal in Chandrasekhar's own words the depth of his pursuit of science as well as his personal struggles. This book is an important addition to the three previous volumes by Kameshwar C. Wali, including Chandra, A Biography of S. Chandrasekhar, S. Chandrasekhar: The Man Behind the Legend, and A Quest for Perspectives: Selected Works of S. Chandrasekhar (With Commentary), Volumes 1 & 2. Included in the correspondence are Chandra's thoughts and feelings about his student days in India and Cambridge, his trials and tribulations in the competitive world of British academia, his travels to Russia and Germany, and his unexpected and historic encounter with Sir Arthur Eddington. The book also includes rare correspondence and conversations with Lalitha, Chandrasekhar's wife of over sixty years. The letters and conversations with her reflect her own views of their life. She, a student of physics herself, eventually gave up her own work in science to become an integral part of Chandra's life. As Chandra wrote, "The full measure of [of my indebtedness] cannot really be recorded; it is too deep and too all persuasive. Let me then record simply that Lalitha was the motivating source and strength of my life." This new book adds a significant personal dimension to an extraordinary scientist and will give the public a deeper understanding of the man behind the legend.