Percutaneous biopsy is the radiologist's most frequently performed interventional procedure. Its success is due to a number of factors, including rapid advancements in biopsy needle technology which have allowed interventionalists to improve upon the efficacy, safety, and accuracy of the procedure. The characteristics of these needles are discussed, with reference to specific applications of the different needles, and the safety and diagnostic information that can be obtained. A thorough knowledge of the different needles available is important for a well-equipped radiology department, and a better choice of the most appropriate needle for each procedure.