Percutaneous renal biopsy is a valuable tool in the definitive diagnosis of a variety of kidney diseases. Advances in the design of biopsy needles as well as the availability of real-time ultrasound guidance for the procedure, has greatly reduced complication rates. In this review, we summarize the contemporary practice of real-time ultrasound-guided percutaneous biopsy of the native and transplant kidneys. Practical tricks in enhancing this method of biopsy are presented. Non-percutaneous techniques in specific settings are also discussed.