A metal or plastic bracket intended to be applied to a hand-held ultrasound (US) transducer for the repeatable positioning (detach from/reattach to same place) of an electromagnetic (EM) sensor and/or needle guide on the transducer. It may be used in conjunction with an EM device tracking system and is intended for applications involving needle guidance and tracking such as ablation, core tissue biopsy, fluid aspiration, therapeutic delivery and vascular access. Disposable needle guides and imaging-supportive devices (e.g., US transducer cover/gel) may be included with the positioner; the transducer and sensor are not included. This is a reusable device.