Consultancy is an area of practice which, until now, has had few resources for training and continuous professional development aimed specifically at health psychologists. This chapter outlines the structure and content of The Palgrave Handbook of Consultancy in Health Psychology. In addition to existing practitioners, health psychologists who have not yet embarked on consultancy will find the book of interest. It contains 16 case studies across private, public and third sectors and across a variety of health domains; each case study focuses on one consultancy process from the Framework for Consultancy in Health Psychology, which is presented in a later chapter (Chap. 3 ). The authors also introduce 11 chapters on topics of importance to successful health psychology consultancy including ethics, multidisciplinary working and working with vulnerable service users, and eight topics focusing on practical issues in working as a health psychologist in a business context. The authors provide a definition of consultancy in health psychology drawing on decades of experience of practice and on the wider consultancy literature, explaining why the handbook was curated, and how best to use it.