Aim: This study aimed to assess colorectal clinicians' knowledge and understanding about the risks and benefits of weight management, to document current practice and to identify perceived barriers to providing lifestyle advice to colorectal cancer survivors Methods: Questionnaires were sent to 768 clinicians (doctors and nurses) working in colorectal cancer, identified from professional databases. These data were complemented by in-depth interviews exploring opportunities and barriers to giving lifestyle advice. Results: A total of 323 replies were received (42% response rate) and twenty respondents completed in-depth interviews. Half (52%) reported they were familiar with guidance for lifestyle advice for cancer survivors. Most (77%) thought reducing weight was important for improving the health of those who were overweight and 75% thought it appropriate to offer lifestyle advice to people with body mass index (BMI) over 30kg/m2. Half (50%) reported that weight reduction was an important service priority for normal clinical practice Half (50%) of respondents said that they would value additional training in this area. Interview data revealed that current practice is influenced by the lack of evidence for the impact of weight management, and a belief that "weight gain is good and weight loss bad" in the cancer setting. Patient sensitivity, time available, role constraints and lack of skills in weight management were also factors. Conclusion: There is an awareness of the importance of weight management amongst colorectal clinicians and some indication of advice being provided. However, current perceptions, knowledge and skills suggest scope for further training. © 2013 The Authors. Colorectal Disease © 2013 The Association of Coloproctology of Great Britain and Ireland.