The current generation owes a moral and political obligation to the next generation and beyond , in terms of their real inheritance: the three interlinked existential crises represented by climate change, the multiple crises of the global environment and the conventional and nuclear arms race. This book is an attempt to reach out to the next generation to start shaping their own collective future through the greening of socialism on a global basis as an affirmative survival response to these crises which will have to be confronted in the course of the twenty-first century. It starts with a clear recapitulation of the major historical event-structures of the nineteenth and twentieth centuries which have been responsible for the genesis of these crises and links them to the possible choices and actions for the next century and beyond. These crises are no longer separable in terms of the consequences they entail for global humanity. Nor is it possible to separate our relationship with Nature as a whole from our relationship with each other at a global level. Consequently, the resolution of these crises is no longer a matter of mere technical or economic fixes, they will involve the major part of humanity as actors intervening into shaping their own future. The decisive moment for social and political change is fast approaching, with a clear choice to be made between systemic change or continuing with fragmented systems which are inexorably driving us towards the possibility of human extinction along with the extinction of major life-forms on earth. The building blocks of a desirable and sustainable future are already available to us but the powerful and entrenched economic and political structures of the world are in continuous denial of the possibilities of the future through systemic changes. This book lays out the above argument in a concise and logical framework that ranges across several disciplines from political economy and history to ecology and the sciences and technology. It is then up to the next generation to make their own choices about the future in the light of the mounting evidence about the urgency of systemic change. The decisive moment is now. This book is an honest account linking the past, the present and the likely future. It is a challenging read for those who will rise to the challenge.