The recent progresses in targeted therapy have been successful to present a more precise and effective therapeutic option for the management of breast cancer, specifically the advanced cases. Considering the heterogeneity of breast cancer, a thorough understanding of the molecular, genetic, and immunological behavior of tumor cells as well as tumor microenvironment is the most imperative feature to reaching anticipated therapeutic accomplishment with targeted or immune therapy. This thesis focuses on emerging targeted therapies such as anti-human epidermal growth factor 2 (HER2) therapy, endocrine therapy (ET), cyclin D kinase 4/6 (CDK4/6) inhibitors, phosphatidylinositol 3-kinase (PI3K) /protein kinase B (AKT) /mammalian target of rapamycin (mTOR) pathway inhibitors, Poly ADP-ribose polymerase (PARP) enzyme inhibitors, programmed cell death protein1 (PD-1)/ programmed cell death ligand 1 (PD-L1) inhibitors, and cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) inhibitors, and their challenges and proposed solutions.