Mike Glazer is Emeritus Professor of Physics at the University of Oxford and Visiting Professor at the University of Warwick. He was born on May 1st 1943. His PhD research between 1965 and 1968 was under the supervision of Kathleen Lonsdale at University College London, working on the crystallography of organic mixed crystals. In 1968-1969, he was a Fellow at Harvard University, and then from 1969 to 1976 he was at the Cavendish Laboratory, Cambridge. In 1976, he was appointed Lecturer in Physics at the Clarendon Laboratory Oxford and as an Official Fellow and Tutor at Jesus College Oxford. Mike Glazer's research has mainly been in understanding the relationship between physical properties of crystals and their structures. He is perhaps best known for his classification system for tilted octahedra in perovskites. He is also one of the co-founders of Oxford Cryosystems Ltd, which supplies the world market in low-temperature apparatus for crystallographers. He is currently Editor of the Newsletter of the International Union of Crystallography. Abstract: The field of Crystallography is one of the oldest of scientific disciplines, and yet it continues to make important advances today and into the future. In this talk, I will trace the history of some important ideas that have led to some basic understanding of the structures of crystals before experimental techniques evolved to enable these theories to be tested. In the 20th century, the discovery of X-ray diffraction by crystals has led to the formation of a whole new discipline, namely X-ray Crystallography. This discovery has since then expanded to include neutron and electron scattering and has increased our knowledge of materials and biological systems. As a result, many Nobel Prizes have been awarded for work relying on crystallographic studies. Over the last 100 years many new experimental techniques have arisen, including the use of synchrotron radiation, free electron lasers and very recently major advances in the use of electron microscopes.