The full promise SAFIR will only be realized if detectors of matching capabilities are available. SAFIRscience will require significant effort in detector development, and an important effort under this proposal will beidentification of detector needs. It has been well demonstrated that early investment in key technologies can paylarge dividends in cost and success. The study will flow down the science requirements for SAFIR into detectortechnology needs. For example, in order to take advantage of the low background from SAFIR, detectors with NEPsless than a few x 10-19 W Hz-1/2 will be needed for cameras, and lower for spectrometers