Around 2 million people are living with cancer. The NHS has a responsibility to help patients to recover from hospital treatment. One of the ways of doing this is through rehabilitation. Cardiac rehabilitation programmes are already routinely offered to people who have had a heart attack. It is likely that people with cancer could benefit from a similar type of rehabilitation and support. However, before carrying out a large study to test this, it is important to assess whether the existing cardiac programme meets the needs of patients recovering from colorectal cancer and learn about their experience of participating in cardiac rehabilitation. Before we carry out a larger and more expensive study, we need to know: If it is possible to refer cancer patients to cardiac rehabilitation; Whether the rehabilitation programme works in the way intended; and If the programme is viewed as acceptable and helpful by patients and clinicians. WHAT IS THE SERVICE WE WISH TO STUDY? The service is a 10 week post-hospital cardiac rehabilitation programme delivered by trained cardiac rehabilitation physiotherapists who will receive additional training from a cancer-exercise specialist. The mixed classes of cancer and cardiac patients will have some components tailored to meet the needs of cancer patients. Patients will attend for 1 or 2 hours each week for exercise training and education (e.g. stress management, diet, smoking cessation, benefits of exercise and relaxation). Some sessions on cardiac disease will be replaced with sessions about cancer and will be delivered by a cancer nurse to cancer patients separately. STUDY The study will take place in three hospitals in Inverness, Stirling and Cardiff and will be conducted in two stages: Stage 1: Twelve colorectal cancer patients will be recruited from one out-patient clinic and invited to attend a cardiac rehabilitation programme. They will complete a questionnaire about their health and levels of physical activity and wear an accelerometer (similar to a wrist-watch) for 7 days to record the level of exercise. They will do this twice - at the start and then at the end of the programme. Views about participation in the programme, completing the questionnaire and wearing the accelerometer will be collected in face-to-face interviews with patients and their nominated family member. In addition, 6 nominated family members of the cancer patients, 6 cardiac patients and 6 clinicians will be recruited to participate in an interview to determine their views on involving cancer patients in cardiac rehabilitation. The programme and research instruments and procedures will be modified in light of the findings from this stage. Stage 2: Approximately 66 colorectal cancer patients will be recruited from 3 out-patient clinics and randomly divided into two groups to receive either cardiac rehabilitation or a leaflet about recovering from colorectal surgery. Questionnaire data on health and physical activity and accelerometer data will be collected three times immediately before starting rehabilitation, on completion of the programme and 3 months later. 24 patients will be interviewed about their experience of taking part in the programme. 12 clinicians will also be interviewed about their views of involving cancer patients in a cardiac rehabilitation programme and their views on running the study. Finally, we will work out how much this rehabilitation programme would cost the NHS if it was going to be offered to cancer patients.