INTRODUCTION: Sustainability of healthy lifestyle behaviours following participation in a research-based supervised lifestyle intervention programme is often poor. This study aimed to document factors reported by overweight and obese individuals with Type 2 diabetes as enhancing or impeding sustainability of lifestyle behaviours following participation in such a programme. METHODS: Thirty patients who completed a 16-week research-based supervised lifestyle intervention programme, incorporating a structured energy restricted diet with or without supervised resistance-exercise training underwent a semistructured qualitative interview about their experiences in maintaining programme components after 1 year. RESULTS: Participants maintained 8.8-8.9 kg of the 13.9-6.6 kg weight loss achieved with the research-based supervised lifestyle intervention programme. Only 23%of participants indicated continuation of the complete diet programme. Desire for ‘variety’ (33%) and increased portion size (27%) were the most commonly reported reasons for discontinuation. Participants who undertook supervised exercise training during the programme indicated access to appropriate programmes/ facilities (38%), more affordable gym membership (21%) and having a personal trainer/motivator (17%)would have facilitated exercise continuation. CONCLUSION: In overweight and obese individuals with Type 2 diabetes, success of the research-based supervised lifestyle intervention programme was perceived as being primarily due to high levels of professional support and supervision, the discontinuation of which subsequently presented difficulties. The interview data provide insight into what people experience following the completion of a research-based intensive lifestyle intervention programme and suggest that programmes assembled for research purposes with the emphasis on compliance may not necessarily promote sustainable change. ; T.P. Wycherley, P. Mohr, M. Noakes, P.M. Clifton and G.D. Brinkworth