This introduction presents an overview of the key concepts discussed in the subsequent chapters of this book. The book examines the impetus for doctrinal change in conventional doctrine. It deals with Limited War theory beginning with Clausewitz's understanding of war and necessary nuclear related caveats added by Bernard Brodie followed by a review of the historical development of the Limited War concept in the US and in India. The book then deals with the doctrines in general and 'Cold Start' in particular. It also deals with India's regional strategic predicament in order to bring out how land warfare doctrine in particular has adapted to its regional strategic circumstance. The book discusses the political factor in terms of strategic culture at state level. It explores how organisational culture, organisational processes and bureaucratic politics account for change in doctrine. The book explores the relative validity of the three drivers of doctrinal change at the respective levels of analysis: structural, state and organisational.