Since World War II, the ever improving sophistication in missiles capabilities in terms of payload, range, accuracy etc. had led to an unprecedented and unending arms race and proliferation. The obvious and connatural unificationof ballistic missile and nuclear bomb shaped it as the most high profile weapon system that has dominated the worldpolitics and security paradigm so intricately. With the new perception of deterrence and threat, the warfare has taken a new dimension.Concurrently; Ballistic Missile Defence as a concept evolved during 1960s. However, the two superpowers deploying thousands of intercontinental ballistic missiles (ICBM) remained effective stability tool during Cold War and development of missile defences were restricted through the regime of arms control treaties as in the perception of the bipolar world, Anti Ballistic Missile Systems will weaken the stability stratagem anchored on policyof Mutual Assured Destruction. Nevertheless, development of BMD system continued and remained one of the most controversial issues in the world politics and international security paradigm. Ballistic missile defence, from its concept has grown manifold. Initially, missile defences have been put into operation centred on destroying the launch platform through ground based nuclear tipped ballistic missile system. With increased sophistication in missile technology, the challenge is thrown to intercept an incoming ballistic missile in its boost phase, mid course phase or in terminal phase. Notwithstanding, there are many technological constraints to arrive at a desired comprehensive shield to provide effective and efficient security. A debate followed world over on efficacy and viability of such a defensive shield as the technology is yet to be proven and that is prohibitively costly. The debate also brings forward the environmental issues, weaponisation of space and lethality of missile defence against its counter measures and issues of proliferation and arms control. Despite all such criticism and debates over its viability, the urgency towards evelopment and deployment world over is alarming. With the phenomenal technological sophistication and growth, missile defence has acquired the status of a frontier of the 21st century, impacting global strategic stability as well as arms control. This book is an attempt to study the ballistic missile defence concepts, systems, technologies and its growing influence as a revolutionary military system and a strategic political tool. This study posits various strategic issuesin context to implications of missile defence development and deployment.