Yeon Hee Park, MD, PhD, Samsung Medical Center, Seoul, Korea, talks on treatments for estrogen receptor-positive metastatic breast cancer, mentioning CDK4/6 inhibitors and newer agents such as GDC-9545, which may potentially replace standard of care aromatase inhibitors. Prof. Park also emphasizes on the need to find strategies to overcome resistance to CDK4/6 inhibitors. This interview took place at the European Society for Medical Oncology (ESMO) 2021 congress