99mTc diphosphonate bone scanning has proved to be a sensitive, though nonspecific, way of detecting a wide variety of metabolic bone disorders. Classic scan appearances of generalized increased tracer uptake throughout the skeleton are found in many types of metabolic bone disease, and whole-body retention measurements can be used to detect early forms of disease. Focal disease identified on bone scanning such as pseudofractures and brown tumors are clearly identified on the 99mTc diphosphonate bone scan, with isotope scan changes preceding radiological changes by up to 18 months. The use of whole-body retention measurements will further increase sensitivity of detection in patients with metabolic bone disease.