This guidance provides detailed recommendations for manufacturers seeking marketing clearance of diagnostic ultrasound systems and transducers.  In addition to outlining regulatory approaches for certain diagnostic ultrasound devices, this guidance document describes the types of modifications to a diagnostic ultrasound device for which FDA does not intend to enforce the requirement for a new premarket notification (510(k)).  As before, manufacturers who submit 510(k)s and receive marketing clearance will continue to be exempt from the Electronic Product Radiation Control (EPRC) reporting requirements in 21 CFR 1002.12, for diagnostic ultrasound devices, as described in the notice to industry entitled “Exemption from Reporting under 21 CFR 1002” dated February 24, 1986.