This is the first publication (in German or English) of Hermann Minkowski's three papers on relativity together: (i) The Relativity Principle - lecture given at the meeting of the Goettingen Mathematical Society on November 5, 1907 (the first English translation); (ii) The Fundamental Equations for Electromagnetic Processes in Moving Bodies - lecture given at the meeting of the Goettingen Scientific Society on December 21, 1907 (new translation); (iii) Space and Time - lecture given at the 80th Meeting of Natural Scientists in Cologne on September 21, 1908 (new translation).