ES2013 marks the 25th anniversary of the series of workshops initiated in 1989 by David M. Ceperley and Richard M. Martin. The workshop series brings together participants in electronic structure theory from universities, colleges, and government and industrial labs around the world. The presentations describe new methods for computing previously inaccessible properties of materials, breakthroughs in computational efficiency and accuracy, and novel applications of these methods to the study of molecules, liquids, and solids. The program consists of invited oral presentations and contributed posters.