A method is disclosed for the delivery of therapeutic agents into tissues, blood vessels, and body ducts of the human body. A novel catheter enables controlled directing of emitted drug delivery to assist control of drug dwell time in targeted areas. One coaxial catheter embodiment provides capability for locating an outer lumen of the system into the target region, with localization of said outer lumen carried out by use of appropriate medical imaging modalities. In one embodiment, an inner lumen of the catheter means is primed with the agent to be delivered, and recirculated flow of the agent through pluralities of appropriately positioned port holes on the two lumens then occurs via one or more active and/or passive flow driving and guiding techniques intrinsic to the design of the coaxial catheter system. Another coaxial catheter embodiment carries and emits agent in an outer cannula and recaptures agent plus liquid or fluids in the body (such as blood, bile, serum, stable (non-flowing) liquid or kinetic liquid) in an inner cannula.