Social marketing is receiving unprecedented focus and support from government, the private sector and charities internationally. Social marketing attempts to educate people in the hope that they will make ‘informed’(i.e. healthy) choices regarding diet, lifestyle and health related issues. The effective application of social marketing principles can be complex and controversial. Social marketing planning cannot be reduced to a simple set of actions on a checklist; there is no single strategy for success and strategies that have proved successful with one population may not transfer to other populations. This text will explore the complexities involved in researching, planning and implementing effective social marketing programmes, using illustrative cases from both successful and unsuccessful real-world programmes.