Minimally invasive percutaneous medical procedures are widely accepted in current clinical practice. However, with current techniques, the procedures are challenging and a high level of expertise is required to perform them successfully. This paper presents a novel steerable needle device for percutaneous interventions that allows the physician to steer the tip of the needle during insertion which eases the challenge associated with reaching the target. The steering concept uses slightly modified, off-the-shelf medical biopsy needles. A controlled lateral steering motion of over 30 mm during a 100-mm needle insertion is demonstrated with a 20-gauge needle in tissue-mimicking phantoms. A hand-held, motorized device has been built that actuates the needle base to produce a desired steering direction and magnitude at the tip. Steering commands may be supplied either by user input or by computer control. For the latter case, a method of software path planning has been developed that automatically steers the needle to a target.