Aims: To investigate the variations in follow-up practice for screen-detected ductal carcinoma in situ (DCIS) in the UK. Methods: A questionnaire enquiring about follow-up practice and the perceived value of clinical follow-up after surgery for screen-detected DCIS was sent to the 74 UK screening centres participating in the Sloane Project. Results: Responses were received from 66 hospitals serving 54 screening centres. These demonstrate wide variations in practice. Clinical follow-up duration ranges from 1 year to indefinite, with the frequency of visits from three-monthly to annually. Formal mammographic follow-up duration ranges from none to indefinite. Mammographic frequency ranges from 1 to 2 years. Follow-up varies according to factors such as size and grade of disease and margin status in 23 units and according to whether adjuvant therapy is given in 23. Seven hospitals perform mammography of reconstructed breasts. Thirty-one centres consider clinical follow-up of DCIS to be of value or limited value whereas 28 consider it to be of little or no value. Conclusions: There is no consensus with regard to the duration and frequency of follow-up for screen-detected DCIS, the contribution of predictive and treatment factors, the use of mammography of the reconstructed breast or the perceived value of clinical follow-up. Published guidelines show no consensus. Multidisciplinary teams involved in the care of women with screen-detected non-invasive cancer should contribute to audits such as the Sloane Project in order to determine the most effective and efficient ways to treat and follow up these patients.