The study of personality requires an unusual feat of mental vision. Those of us who work in this field must focus narrowly on one or more specialized research topics, while simultaneously maintaining a wide-angle view of personality in a broader sense. The day-to-day demands of doing research can make it hard to preserve the broader focus, especially when immediate research projects are progressing well. The aim of this Handbook is to assist researchers, practitioners and students to regard the larger picture of personality research. Recent years have seen a resurgence of interest in personality, directed along lines of research that sometimes converge and sometimes seem to diverge. Our motivation in compiling this Handbook was to provide a general overview of the many areas of study that together define this branch of psychological science – that many of us consider to be becoming increasingly relevant and important in psychology more generally.