<P>From his position as a Senior Fellow, the author addresses in this book the structural challenges and difficulties that predate Covid pandemic: climate change, economic inequality and the demographic challenge. These challenges raise fundamental questions of equity both between and within generations. Their immediate effects are much weaker than their long-term effects, which encourages policymakers to delay. But the cost of meeting them increases over time. These menaces raise complex technical and economic issues; some decisions must be made under great uncertainty. For each of these challenges, solutions exist: why is there little progress and how to turning threats into opportunities?</P><P></P><P>In all cases, technological change is a central aspect, constituting both part of the problem and part of the solution. The solutions the author formulates are of two kinds: policy recommendations and exploratory strategic proposals. Some of the recommendations include measures that ha