An interventional medical diagnosis and/or therapy system is provided. The system provides an interventional imaging system and method which allows for an intervention, to be conducted in accordance with an intervention plan, to be supported and monitored by ongoing imaging, in particular radioscopy, with which, at the same time the effort in calibration and registration is kept low, and which functions without an additional location system. The interventional imaging system includes an imaging device to record intervention data of a body, at least two position markings, capable of being recorded with the imaging device, for the marking of an intervention instrument, a display apparatus to reproduce recorded intervention data and position markings, a navigation facility connected to the display apparatus to load pre-intervention data of the body, in which an intervention location of the body is contained, and for the mutual registration of the pre-intervention data with the intervention data.