There has been a reluctance to treat patients with invasive lobular carcinoma by breast-conserving therapy because of the possibility of increased rates of local recurrence. This study is a retrospective review of 226 patients with pure invasive lobular carcinoma 4 cm or less treated by breast conservation therapy or mastectomy. Local relapse occurred in four of 52 patients (8 per cent) after breast conservation compared with 21 of 174 (12 per cent) after mastectomy. Breast conservation for invasive lobular carcinoma did not result in a higher incidence of local relapse and patients with invasive lobular and ductal carcinomas may be managed in a similar fashion.