By: Nick Turner, PhD and Paula Palacios Fernandez, MScBreast cancer is the most common cancer in women with more than 2.1 million new cases diagnosed in 2018. And with more than 600,000 deaths in 2018, it is the second-leading cause of cancer deaths in women worldwide (WHO). Advances have been made across all stages and sub-types of the disease and provide hope for improved treatment options, lower rates of relapse and better survival outcomes. The development of agents against novel molecular targets, including inhibitors of PARP, CDK4/6, PI3K and immune checkpoints, offers treatment options for patients with previously poor prognoses and treatment-resistant disease. We describe some recent developments below.