A biopsy system (10) comprises a biopsy device (14) and a localization grid plate (96,300), which is configured to localize part of a patient and defines a plurality of round openings (306). A probe (91) of the biopsy device and/or other associated other components may be inserted through a selected one of the openings. The grid plate may thus guide the probe and/or other components as such components are inserted into the localized part of the patient and may further support the probe and/or other components after insertion. The grid plate may thus be used without a targeting cube (104) or other inserted guide. Alternatively, the openings of the grid plate may be configured to receive a targeting guide having a cylindraceous body. The guide body may define passageways for inserting a probe or other components, and may be rotatable to position the passageways to selectively define an insertion axis for the probe.