This book contains selected papers of Prof Nambu who is one of the most
original and outstanding particle theorists of our time. This volume
consists of about 40 papers which made fundamental contributions to our
understanding of particle physics during the last few decades.The
unpublished lecture note on string theory (1969) and the first paper on
spontaneous symmetry breaking (1961) are retyped and included. The book
also contains a memoir of Prof Nambu on his research career.