The Madhouse Effect is, by design, a book that readers can just pick up, skim through, and find a page that both engages and informs. If a reader were to browse only a few pages, my co-author Tom and I might want them to check out the preface. It’s entitled “Why We Wrote This Book.” It provides with a sense of how it is that a climate scientist and an editorial cartoonist would come to collaborate as we did. It conveys the tremendous urgency of acting to avert catastrophic climate change.The closing pages of the book could also be a very good entry point. Here we give the reason for cautious optimism, despite the many challenges that we currently face when it comes to climate action.The Madhouse Effect has newfound prescience. Unforeseen when it was first published in early Fall 2016 is the relevance that the phenomenon of climate change denial now has, after the November 2016 U.S. presidential election.To the extent we might have seemed to have escaped it, we now find ourselves very much back in the madhouse of climate change denial. If previously the clock has been ticking, depending on the new administration’s actions, we may be facing a clock that could run out. That makes the challenge of acting to avert catastrophic climate change even greater now than it was before.That, in turn, makes it even more important that individuals engage in the actions that we motivate in the final chapter of The Madhouse Effect — grassroots efforts to mobilize public concern and support for action, putting pressure on our elected representatives, and encouraging international cooperation.There is still reason for cautious optimism given the progress both in the U.S. and abroad in moving away from fossil fuels. We have seen policy progress at the international level — the 2015 Paris agreement and the commitment to build on it.While Trump and climate-change denying republicans might deal a temporary setback, they cannot ultimately stem the tide — the world has decided it is time to move beyond the antiquated age of fossil fuels. We will solve the problem. If anything, this message of The Madhouse Effect is even more salient now than it was when the book was published.