Introduction and Overview.- A Short History of Nuclear Physics to the Mid-1930s.- The Discovery and Interpretation of Nuclear Fission.- Organizing the Manhattan Project, 1939-1943.- Oak Ridge, CP-1, and the Clinton Engineer Works.- The Hanford Engineer Works.- Los Alamos, Trinity, and Tinian.- Hiroshima and Nagasaki.- The German Nuclear Program.- The Legacy of Manhattan.- Glossary.- Index.