Sir Charles Frank is one of the foremost scientists of the last fifty years. He has made important advances in a large number of different fields in physics, notably the properties of dislocations in crystals. This book is a celebration of his work, with contributions from many of his former colleagues and students. The contributors are all eminent in their particular fields, and the great variety in their contributions demonstrates the vast impact Sir Charles has had on modern physics. The papers range over many of the fields in which Sir Charles has worked. These include crystal growth and crystal properties, liquid crystals, particle physics, metallurgy, polymer physics, materials science, geophysics and the mechanics of the Earth's crust. A major part of the book is concerned with the subject with which he is most closely associated, namely the behaviour of dislocations in crystals. The contributions are mainly of two types. There are reviews of Sir Charles' work, concentrating on his original ideas and extensions of his theories that have been made by other researchers. There are also original contributions describing the outcome of new and ongoing research, showing that Sir Charles' pioneering work is still producing important results. Also included are reminiscences of Sir Charles' life and work at Bristol and elsewhere, with many anecdotes demonstrating his unique approach to research and teaching. Because of the wide-ranging nature of Sir Charles Frank's work, this collection of essays will be of great interest to scientists in a wide range of fields.