Professor Paul M.W. Hackett is a psychologist with an interest in structured ontological accounts, from a philosophical and psychological perspective, of both human and non-human animal behaviour. His research has addressed several applied domains including bird behaviour and his writing has appeared in prestigious journals. He has also published a dozen books, including texts on the research methods in psychology. During the time this book was written, Paul was a visiting researcher in the comparative cognition research group at the University of Cambridge. Paul is a visiting professor in health research methods at the University of Suffolk, a visiting professor in the psychology department at Gloucestershire University and an honorary fellow in the philosophy department at Durham University. Paul also teaches ethnography in the School of Communications at Emerson College, Boston and has homes in Wiltshire and Massachusetts.