This book is a specially edited volume dedicated to the celebration of 100 years of Quantum Mechanics in its 'Copenhagen' final form, triggered by Heisenberg's breakthrough paper of July 1925, for which he was singly awarded the Nobel Prize in Physics in 1932. It contains papers from several contributors on a selection of topics related to the foundations of quantum mechanics, its history and subsequent developments. All the papers are contributions by an international team of experts to a special Heisenberg centenary session of the IQSA Tropea conference in July 2025 in Italy. The book follows a similar volume dedicated to the celebration of the same event at its 50th anniversary in Strasbourg, and provides a generational bridge for physicists, mathematicians, engineers, chemists, biologists, indeed anyone with an interest in the history and the development of quantum physics. In addition to the printed book, numerous original documents such as power-point slides, audio and video recordings as referenced throughout a archived online for the reader to consult at no extra cost. This 100th anniversary printed volume together with its 50th anniversary counterpart should sit on the shelf of all serious students, researchers and historians of science due to their unique scientific, philosophical, cultural and historical value.