A fiducial deployment needle system comprising: an outer sheath having a longitudinal outer sheath lumen; an elongate fiducial-carrying member disposed coaxially through the outer sheath lumen; a plurality of fiducials disposed along a distal portion of the fiducial-carrying member; and a movable structure configured to advance the fiducials distally relative to the fiducial-carrying member; characterized in that: each of the fiducials includes a central aperture engaged around the fiducial-carrying member; the fiducial-carrying member is configured as an elongate delivery cannula with a longitudinal delivery cannula lumen therethrough, and the movable structure is configured as a flexible deployment member; the flexible elongate deployment member includes at least one engagement structure proximally located relative to at least one of the plurality of fiducials; the at least one engagement structure comprises at least one bead fixed to the flexible elongate deployment member; and the system further comprises a stylet disposed through the delivery cannula lumen, wherein the stylet comprises at least one longitudinal groove configured to allow proximal passage of a bead that has been advanced past and around a distal end of the delivery cannula. an outer sheath having a longitudinal outer sheath lumen; an elongate fiducial-carrying member disposed coaxially through the outer sheath lumen; a plurality of fiducials disposed along a distal portion of the fiducial-carrying member; and a movable structure configured to advance the fiducials distally relative to the fiducial-carrying member; characterized in that: each of the fiducials includes a central aperture engaged around the fiducial-carrying member; the fiducial-carrying member is configured as an elongate delivery cannula with a longitudinal delivery cannula lumen therethrough, and the movable structure is configured as a flexible deployment member; the flexible elongate deployment member includes at least one engagement structure proximally located relative to at least one of the plurality of fiducials; the at least one engagement structure comprises at least one bead fixed to the flexible elongate deployment member; and the system further comprises a stylet disposed through the delivery cannula lumen, wherein the stylet comprises at least one longitudinal groove configured to allow proximal passage of a bead that has been advanced past and around a distal end of the delivery cannula. each of the fiducials includes a central aperture engaged around the fiducial-carrying member; the fiducial-carrying member is configured as an elongate delivery cannula with a longitudinal delivery cannula lumen therethrough, and the movable structure is configured as a flexible deployment member; the flexible elongate deployment member includes at least one engagement structure proximally located relative to at least one of the plurality of fiducials; the at least one engagement structure comprises at least one bead fixed to the flexible elongate deployment member; and the system further comprises a stylet disposed through the delivery cannula lumen, wherein the stylet comprises at least one longitudinal groove configured to allow proximal passage of a bead that has been advanced past and around a distal end of the delivery cannula.