Triple negative breast cancer (TNBC) accounts for approximately 15% of breast cancer cases. TNBC is an immunohistochemically defined subtype, with significant diversity within the subtype. Generally TNBC occurs in younger women and is marked by high rates of relapse, visceral and CNS metastases, and early death. Current therapy fails to curtail the innate aggressive behaviour of TNBC in the majority of patients. The poor prognosis coupled with a lack of targeted use of therapies is reflected in the high mortality. In a minority of patients with highly chemosensitive disease, no robust clinical evidence exists to guide use of current cytotoxics. Critical to optimal future management are accurate identification of truly triple negative disease and adequately powered prospective TNBC trials to establish treatment efficacy and define predictive biomarkers.