this book contains 37 papers contributed by former students, colleagues, and friends of professor chris calladine, to mark his retirement.professor calladines research has ranged very widely across the fields of structural mechanics, with a particular focus on the plastic deformation of solids and structures and the behaviour of thin-shell structures, and molecular structures. a distinctive feature of his research has been a strong emphasis on rigorous formulations that provide both physical insights and accurate prediction of observed behaviour. this approach has led to major advances in many areas, and the papers included in this book give powerful illustrations going from the theory of structures (lightweight, adaptive, symmetric) to the design and analysis of shell structures, and the use of physical models in the study of dna and bacterial flagella. this volume will be of particular interest to graduate students, researchers and engineers in structural, mechanical, and aerospace engineering, and also to researchers in molecular biology.