This book examines the evidence on the effectiveness and cost-effectiveness of health promotion policies and projects, with particular emphasis on the UK. As an introduction, this chapter clarifies the key concepts in the health promotion literature such as ‘new public health’, civil society, poverty and empowerment. It first considers the potentially disputed assumption that ‘health’ is an unequivocal concept before discussing the social determinants of health, the emergence of a ‘new public health’ in the UK that consists of health promotion as a model of health policy, and the role of civil society in health promotion. It also explains what poverty is, the impact of public health and health promotion interventions, the purpose of health promotion, and motives for improving people's health (such as empowerment, charity, economics). Finally, it reflects on the future for health promotion.