 The use of radiation in medical imaging is essential for detecting diseases and saving lives. But it must always be justified. This means the test must be carefully chosen and only performed when needed, particularly when it comes to children and pregnant women. This protects patients from unnecessary radiation. I decide for my patient which exam is the right one for them. When do they need the procedure and do they need the procedure at all? Other options that involve less or no radiation may include diagnostic procedures such as magnetic resonance imaging, known as MRI. If there is another modality which does not use ionizing radiation and would be good for diagnostic values in that patient, that should be used instead. The whole medical team needs to work together to ensure that all radiation exposure is justified without compromising medical benefits. To ensure my patient's safety, I usually call my other colleagues, especially radiologists, to discuss which exam is the most proper one for my patient. Patients can help medical professionals by sharing information about any previous exams. If previous records and images are not available but can be made available, then we do not perform any further imaging unless clinically justified. Professional societies and health authorities have developed guidelines that help physicians select the right exam at the right time. The IAEA also assists countries on justification with training and educational resources.