This book gives an accessible overview of the 70-year history of nuclear fusion research and the vain attempts to construct an energy-generating nuclear fusion reactor. It shows that even in the most optimistic scenario nuclear fusion, despite the claims of its proponents and the billions being spent on research, will not be able to make a sizable contribution to the energy mix in this century. The important consequence is that nuclear fusion will not be a factor in combating climate change, since the race for carbon-free energy will have been won or lost long before the first nuclear fusion power station comes on line.