The physics basis for almost all the diagnostics planned for ITER is reasonably well in hand. However, the radiation environment near the ITER plasma creates unique challenges for diagnostic engineering. To illustrate this, we take a virtual tour of the ITER complex, beginning in the control room and diagnostic hall, where familiar components are configured much as they are in existing facilities. As we move more closely to the plasma, however, crossing into different zones for access and hazard confinement, the nuclear and plasma edge environment drives diagnostic designs in new directions, with new uncertainties. In each region, anticipated advances in supporting technology will be described, and new strategies for diagnostic implementation will be explained. The need for new standards of reliability will be highlighted, due to the difficulty of robotic maintenance and repair.