Parallel with current applications in minimally invasive surgery, the introduction of new imaging modalities, and the availability of high-performance computing, new image-guided therapies are being developed at an impressive rate. Indeed, across a broad front of imaging technologies, rapid advances are being realized. Vastly refined technology for processing and using images, as well as improved therapeutic end-effectors, have no doubt hastened this remarkable progress. At the same time, advances in clinical evaluation and complementary technologies will provide the necessary infrastructure through which IGT can be applied in diverse therapeutic settings--from the already well-established neurosurgical applications to the thermal ablation of tumors in organs other than the brain. That IGT is more efficient and effective and less expensive than conventional surgery has been confirmed both in extensive, long-term studies and in ongoing, revolutionary applications in the operating room. We have laid critical groundwork with this extraordinary technology and have now begun to realize quantifiable benefits in terms of improved surgical and patient outcomes.