Radiology is a core discipline of modern medicine that integrates theoretical foundations with clinical practice across the health sciences. This chapter reviews radiology’s place in health sciences; the scientific bases of imaging; its contributions to clinical decision-making; the scope of interventional radiology; radiation safety and ethical principles; and future directions. Radiology rests on principles from physics, biomedical engineering, and molecular biology, encompassing the operating principles of X-rays, computed tomography, magnetic resonance imaging, ultrasound, and nuclear medicine. These principles not only underpin technological advances but also provide a rational framework for selecting the most appropriate modality in specific clinical contexts. Along the continuum from diagnosis through treatment planning to follow-up, radiology is indispensable. In acute stroke, trauma, oncology, and cardiology, imaging findings directly inform multidisciplinary management. Interventional radiology extends the specialty beyond diagnosis to minimally invasive procedures—including diagnostic biopsies, tumor ablation, vascular interventions, and musculoskeletal applications—thereby reducing morbidity and length of stay while enhancing patient safety. Beyond technical proficiency, adherence to the ALARA principle, protection of pediatric and pregnant patients, informed consent, and preservation of confidentiality anchor a patient-centered and ethical practice. Emerging advances—artificial intelligence, functional and molecular imaging, radiogenomics, and simulation-based training—are positioning radiology at the center of personalized medicine, with pivotal influence at every step of clinical decision-making.