The 2019 edition of the annual ESMO meeting proved to be a grand cru when it comes to breast cancer studies. In early triple negative breast cancer (TNBC), the KEYNOTE-522 trial demonstrated a significant improvement of pathological complete response rate with the addition of pembrolizumab to neoadjuvant chemotherapy, irrespective of PD-L1 status. In addition to this, the prognostic value of tumour-infiltrating lymphocytes was confirmed in a pooled analysis of patients with TNBC who did not received adjuvant chemotherapy. In the field of metastatic breast cancer, much attention went to overall survival data that were presented for the CDK4/6-inhibitors ribociclib and abemaciclib in combination with fulvestrant (MONALEESA-3, MONARCH 2). Interesting results of the phase III BROCADE3 trial were presented in which the addition of the PARP inhibitor veliparib to carboplatin and paclitaxel was evaluated in patients with advanced HER2-negative breast cancer and a germline BRCA mutation. Regarding checkpoint inhibitors in metastatic TNBC, a read-out of a phase III trial with pembrolizumab compared to standard chemotherapy in second- and third-line was presented, as well as important translational data on different immunohistochemical PD-L1 assays from IMpassion130. Finally, two oral presentations focused on the use of CDK4/6-inhibitors in different combination regimens in metastatic HER2-positive breast cancer (MonarcHER) and in TNBC.