Recent years have witnessed the intensification of international debates on Iranian nuclear programme. This book aims to further enrich the understanding on the issue of nature of Iranian nuclear programme that Iran claims to be meant for peaceful purposes, while the western powers suspect the Iranian intent and appear to be determined to block its nuclear ambition. It attempts to situate the Iranian nuclear discourse and international debates concerning the nature of Iranian nuclear programme within the emerging contour of post 9/11 world order. Within this framework, the book seeks to capture the orientations, engagements and responses of the major powers of the world as well as regional powers towards Iran, particularly its nuclear programme in post 9/11 period.