This volume contains the proceedings of MPC 2004, the Seventh International Conference on the Mathematics of Program Construction. This series of c- ferences aims to promote the development of mathematical principles and te- niquesthataredemonstrablyusefulinthe processofconstructingcomputerp- grams, whether implementedinhardwareorsoftware.Thefocus isontechniques that combine precision with conciseness, enabling programs to be constructed by formal...