Brachytherapy (BT) is a core cancer treatment modality that delivers targeted radiotherapy through the placement of radioactive sources inside or near the area to be treated. This provides a very conformal distribution of dose that minimizes radiation exposure to normal organs. This review introduces healthcare professionals (nurses, nurse navigators, public health practitioners, family physicians, and others) to the principles, applications, and future directions of BT. It covers the intent of treatment in oncology, the different types of BT, conditions that are treated with BT and the characteristics of common BT radioactive isotopes. BT’s unique characteristics allow physicians to use it in curative and palliative settings for a wide range of malignant and benign indications. Despite its importance, there are still challenges in terms of accessibility and awareness, highlighting the need for comprehensive education and specialized training in this area. In view of the rising incidence of cancer, the demand for qualified brachytherapists is expected to rise accordingly, given its essential role in cancer care. Furthermore, emerging areas in BT such as the implementation of artificial intelligence and 3-dimensional (3D) printing technology hold promise for improving the accuracy and efficiency of this modality.