The relativistic cosmologists who gathered at the NATO Advanced Research Workshop on `The Origin of Structure in the Universe' to assess the present status of our knowledge on the formation and evolution of structure had much to discuss: in particular, only two days before the conference began on April 27, 1992, the result of the analysis of the first full year of data from the Cosmic Background Explorer Satellite confirmed the theoretically predicted anisotropy in the microwave background radiation, thus opening a new era in observational cosmology. The eighteen papers included here give the reader the very latest views of the foremost cosmologists, using such approaches as multifractal analysis, gauge invariance, Hamiltonian diagonalisation in minisuperspace, string theory, statistical analysis, and topological defect theory.