Many benign proliferative breast lesions have been described in pathology and surgical literature. Several observational studies have examined the natural history of these lesions, and obtaining higher-quality data on this topic is unlikely. Nevertheless, there are proliferative breast lesions for which the current literature is unanimous regarding the increased future breast cancer risk associated with them. These lesions include atypical ductal hyperplasia, atypical lobular hyperplasia, classic lobular carcinoma in situ, florid lobular carcinoma in situ, pleomorphic lobular carcinoma in situ, and atypical papilloma. Understanding the implications of diagnosing these lesions through core biopsy or excision is crucial to ensure appropriate referral of these patients for breast cancer risk assessment and risk reduction counseling