The 2021 edition of In Our Hands is the primary text being used by teachers across the United States in the "Climate Essentials" program offered by the Presidio Graduate School. It succinctly: • Summaries the challenges we face from global warming and climate change; • Presents two futures for the human race, both looking back from 2050. One shows what we did that solved the crisis in time; the other, entitled "The Road to Ruin", shows how the human race collapsed economically, socially and politically in a mere thirty years; • Provides practical actions individuals can take in their personal, community and professional lives to be part of the solution rather than the problem; • Provides links to 150 carefully selected research papers, books and documentary films on all the topics covered in the book, from projections of global warming and sea level rise by the world's leading climate scientists to the decimation of the world's land, fresh water and ocean resources; from the coming water wars in the U.S. and abroad, to the massive global climate refugee crisis that will soon dwarf the refugee crisis we are already experiencing.