 The early detection of diseases greatly increases the chance for effective treatment. Some medical imaging techniques use radiation to create visual representations of the inside of the body. These can use x-rays alone or can be combined with medicines that contain radioactive materials. These radiopharmaceuticals are taken up by the organ or part of the body of interest. The radioactivity emitted from these medicines is detected by special devices and provides information on the location and spread of a disease. Radiotherapy is one of the most widely used methods for cancer treatment. It uses radiation to destroy tumours. Some cancers can also be treated with radiopharmaceuticals. These can be taken orally and cancerous cells are destroyed through their radioactivity. Following treatment for cancer, nuclear techniques can be used to monitor the progress of the therapy. Whether for diagnosis or treatment, the use of radiation in medicine must be carefully controlled. Too little radiation can be ineffective while too much can be harmful. So the medical teams that use radiation medicine must be properly trained and prepared. For over 60 years, the International Atomic Energy Agency, the IAEA, has been supporting the safe and effective use of nuclear techniques in medicine around the world. The IAEA helps countries to set up medical centres that offer radiation medicine services and to procure the essential equipment needed to deliver high quality care and treatment. It supports national efforts to produce and prepare radiopharmaceuticals for diagnostic and therapeutic purposes. The IAEA facilitates training for international medical professionals and students and offers remote learning via its online resources such as the Human Health Campus, which is used by health professionals all over the world. Safety standards developed by the IAEA protect patients and medical staff from the potential harmful effects of radiation. And the IAEA assists when radioactive sources used in medicine are no longer needed and must be stored or disposed of safely and securely. An IAEA laboratory plays a major role in achieving consistency in radiation dosimetry worldwide. This dosimetry laboratory offers services that ensure the machines for cancer treatment are calibrated correctly and the patients receive the right dose of radiation. With IAEA support, countries can provide the safe and quality healthcare all people all over the world deserve.