Since their foundation in 1975, the Marcel Grossmann Meetings (on Recent Developments in Theoretical and Experimental General Relativity, Gravitation, and Relativistic Field Theories) provide opportunities for discussing recent advances in gravitation, general relativity, and relativistic field theories, emphasizing mathematical foundations, physical predictions, and experimental tests. The objective of the MG meetings is to elicit exchange among scientists that may deepen our understanding of spacetime structures and review the status of ongoing experiments aimed at testing Einstein's theory of gravitation, either from the ground or from space.