This book explores nuclear power plants which stand on the border between humanity’s greatest hopes and its deepestfearsforthefuture. Atomic energy offers a clean energy alternative that frees us from the shackles of fossil fuel dependence, while also having lived through the disasters of the quake-ruptured Japanese power plant now spewing radioactive steam, and the dead zone surrounding Chernobyl’s concrete sarcophagus. Topics discussed include the investigation of materials and components obtained from nuclear power plants decommissioning; high-temperature gas-cooled reactors; the impact and effects of the ongoing discussion on the nuclear phase-out in Germany; modeling of corrosion product activity in primary circuits of pressurized water reactors and the fundamental stability analysis of hypothetical boiling and pressurized water reactors.