There has been little investigation of the issues associated with caring for patients presenting for cardiac surgery with a comorbid diagnosis of diabetes although there is some evidence that the diabetes management is suboptimal. This study aimed to identify issues that patients and cardiac specialist nurses experience with the provision of inpatient services for people undergoing cardiac surgery who also have type 2 diabetes. A qualitative interpretive design, using individual interviews with patients and nurses, provided data about some of these issues. The study found that nurses had high levels of confidence in their cardiac care but little confidence in diabetes management. Patients described concerns about their diabetes care and treatment regimens. A ‘typical journey’ for a person with diabetes undergoing cardiac surgery was identified. The findings support the need to build increased capacity in specialist nurses to support diabetes care as a secondary diagnosis.