Breast cancer is a heterogeneous disease with various molecular subtypes that behave differently due to their biology. Risk factors for breast cancer exist, as do preventative strategies in those classified at higher risk. The establishment of the national screening program has led to earlier detection of breast cancers, and this has led to improved outcomes, with the repercussions of over-diagnosis in some patients. There has been an increase in the diagnosis of ductal carcinoma in situ. Management of breast cancer involves local treatment of the breast disease and systemic treatment of the potential (unknown) oligometastatic disease. Local treatment may be mastectomy with or without reconstruction, or breast-conserving surgery and axillary surgery (sentinel lymph node biopsy and, less commonly, axillary dissection). Adjuvant radiotherapy is used to reduce the risk of residual disease in the breast or regional lymph nodes, while adjuvant systemic therapies are used to reduce the risk of distant recurrence.