X-PERT, the acronym for eXpert Patient Education versus Routine Treatment, is a diabetes self-management programme. This thesis explores a different approach to patient education. It begins with an overview of the epidemiology of Type 2 diabetes and exploration of health behaviour models. A systematic review of group-based, self-management diabetes education programmes is then presented. The tutor’s manual for the expert patient programme “X-PERT” is outlined. The design of the clinical trial was to invite the intervention group to attend the X-PERT Programme but to make individual appointments for the control group. The X-PERT trial tests the hypothesis that delivery of a professional-led, diabetes self-management programme based on empowerment and activation would: develop the skills and confidence for diabetes self-management; improve clinical, lifestyle and psychosocial outcomes; meet the International Diabetes Federation standards for diabetes education. The results support the hypothesis with statistically significant findings. X-PERT is an effective approach that should be offered to all people with diabetes as an integral part of their diabetes treatment.