We give an overview of the baseline detector system for SAFARI, the prime focal-plane instrument on board the proposed space infrared observatory, SPICA. SAFARIs detectors are based on superconducting Transition Edge Sensors (TES) to provide the extreme sensitivity (dark NEP$le2times10^{-19}rm W/sqrt Hz$) needed to take advantage of SPICAs cold (<8 K) telescope. In order to read out the total of ~3500 detectors we use frequency domain multiplexing (FDM) with baseband feedback. In each multiplexing channel, a two-stage SQUID preamplifier reads out 160 detectors. We describe the detector system and discuss some of the considerations that informed its design.
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