Global statistics have demonstrated that breast cancer is the most frequently diagnosed invasive cancer and the leading cause of cancer death among female patients. Survival following a diagnosis of breast cancer is grossly determined by the stage of the disease at the time of initial diagnosis, highlighting the importance of early detection. Improving early diagnosis will require a multi-faceted approach to optimizing the use of currently available imaging modalities and investigating new methods of detection. The application of microwave technologies in medical diagnostics is an emerging field of research, with breast cancer detection seeing the most significant progress in the last twenty years. In this review, the application of current conventional imaging modalities is discussed, and recurrent shortcomings highlighted. Microwave imaging is rapid and inexpensive. If the preliminary results of its diagnostic capacity are substantiated, microwave technology may offer a non-ionizing, non-invasive, and painless adjunct or stand-alone modality that could possibly be implemented in routine diagnostic breast care. Author Contributions: Conceptualization, B.M.M., D.O.'L, S.A.E., and M.J.K.; writing-original draft preparation, B.M.M., D.O.'L and S.A.E., writing-review and editing, B.M.M., D.O.'L, S.A.E., and M.J.K.; supervision, M.J.K.; funding acquisition, M.J.K.; All authors have read and agreed to the published version of the manuscript.