The objective of this paper is to provide an overview of Iran’s security environment, challenges and opportunities with specific consideration to the critical nature of US-Iran relations and its current dynamics and future prospects. The paper initially will provide a background on the evolving nature of Iran’s security environment and the historical factors affecting Iranian perceptions and policies. The paper then will address factors shaping Iran’s decision making process and thinking on national security. The paper then will address the US-Iran relations in the context of common interests and areas of contentions and concerns. The final section will be devoted to several key observations on issues concerning Iran and the debate on Iran.