Imaging plays an integral role in the clinical care of patients with breast cancer. This review article focuses on the use of PET imaging for breast cancer, highlighting the clinical indications and limitations of 2-deoxy-2-[18F]fluoro-d-glucose (FDG) PET/CT, the potential use of PET/MRI, and 16α-[18F]fluoroestradiol (FES), a newly approved radiopharmaceutical for estrogen receptor imaging.