Janet Treasure is Professor of Psychiatry at Guys, Kings and St Thomas Medical School (Department of Psychiatry, 5th Floor, Thomas Guy House, Guys Hospital, London SE1 9RT, UK. E-mail: j.treasure{at}iop.kcl.ac.uk). She has specialised in the treatment of eating disorders for over 20 years and is Director of the Eating Disorder Unit of the South London and Maudsley Hospital NHS Trust. The unit is a leading centre in clinical management and training in eating disorders, and is also active in research and development in all aspects of this field. She acknowledges the support of the Nina Jackson Eating Disorders Research Charity in her work, which includes developing the treatment approaches discussed in this article.
Motivational interviewing is a style of patient-centred counselling developed to facilitate change in health-related behaviours. The core principle of the approach is negotiation rather than conflict. In this article I review the historical development of motivational interviewing and give some of the theoretical underpinnings of the approach. I summarise the available evidence on its usefulness and discuss practical details of its implementation, using vignettes to illustrate particular techniques.