Background: Since the widespread use of mammography, the incidence of ductal carcinoma in situ of the breast has increased. Until few years ago the standard treatment was mastectomy, however from the analysis of conservative treatment trials for invasive carcinoma, it was evident that ductal carcinoma in situ could also be treated conservatively. This was confirmed later by randomized trials. Aim: to analyze the experience of our Institution with conservative treatment of ductal carcinoma in situ of the breast. Patients and methods: A search through the data base of our Institution found 69 patients treated with lumpectomy and radiotherapy between the years 1976 and 1997. Results: Twenty three of 69 patients (33%) were diagnosed because of a palpable mass. Eleven of twelve were diagnosed prior to 1990 and 12 of 57 after 1990. With a median follow-up of 48 months local control and overall survival is 97%. None of the patients underwent mastectomy. Conclusions: Conservative treatment of ductal carcinoma in situ of the breast is a reasonable alternative, mainly if we realize that with increasing frequency-the diagnosis is made through mammography and with non-palpable lesions. The results reported in this study are similar to those reported by other centers.