The 11th ISSP International Symposium on “Hydrogen and Water in Condensed Matter Physics” is the 11th in a series of international symposia organized by The Institute for Solid State Physics (ISSP), The University of Tokyo, every two or three years. This 11th symposium will focus on dynamical and electronic properties of hydrogen and water in condensed matter. Hydrogen and water are ubiquitous in the universe and on the earth, but their states of existence are still under intensive research. In addition, hydrogen and water play important roles in material and biological sciences, including proton transfer, hydrogen absorption, catalytic reactions, electrochemistry, ice, gel, among many others. Recent activities in this field have been growing very rapidly using many different techniques; neutron scattering, synchrotron radiation, ultra-fast lasers as well as first-principles calculations. It is highly desirable, therefore, that active researchers assemble in one place, to report new advancements, exchange novel ideas, and discuss new directions in this area.