Excellent book. Anyone interested in the survival of the human race should read this book and take it very seriously.There is a bit of technical data but if you focus on the general thoughts presented, and the depth of the concepts, you will be happy that you spent the time reading it. Everyone focuses on how many people will be killed by the initial blasts but very little on the far reaching near term and long term effects. This book explains it all in very clear, frightening terms.