A method and system are provided for guiding a needle to a target location within a subject. The system comprises a probe and a needle guide. The probe includes two or more transducers that are arranged to direct sound waves toward a target location on a subject. The needle guide can be detachably coupled to the probe, and may be used to maintain the needle within viewing planes of the transducers while the needle is inserted into the subject. To facilitate guidance of the needle, a real-time image of the target region can be produced by overlaying images produced by the two or more transducers. Such a system may provide a more adaptive and reliable way to guide the insertion of a needle, allowing for more sophisticated and fool-proof viewing planes, improved versatility, and more ergonomic needle control.