Nuclear medicine imaging procedures provide a unique physiological view of disease processes that may frequently precede anatomic changes visualized by other modalities. Orthopedic infections are particularly well served by these procedures because the presence of traumatic deformities or hardware in the musculoskeletal structures may significantly interfere with interpretation of images obtained using other modalities, such as computed tomography or magnetic resonance imaging. Several radiopharmaceuticals are currently available which can be imaged in either planar or tomographic formats. When appropriate, multiple radiopharmaceuticals can be imaged either sequentially or simultaneously to better clarify the disease process present in a particular patient. In addition to diagnosing active infection, some of these procedures can be used to follow the response to therapy, or to detect residual infection which may indicate further therapy is required. Newer hybrid imaging techniques which combine nuclear medicine procedures with anatomic imaging show great promise in better localizing infections, and in differentiating infection from noninfectious lesions such as arthritis. Nuclear medicine imaging procedures usually expose the patient to lower radiation doses than computed tomography, and are usually less expensive to perform than other modalities.