Brookhaven is providing the Ring and Transfer Lines Beam Diagnostics for the Spallation Neutron Source (SNS), to be installed at Oak Ridge National Laboratory. The customary diagnostics that will be present include beam position monitors (BPM), ionization profile monitors (IPM), beam loss monitors (BLM), beam current monitors (BCM), coherent tune measurement, and wire scanners. An overview of these systems is presented, along with brief discussions of SNS-specific problems that must be addressed, including unprecedented beam power, large dynamic range, a stringent loss budget, space charge, beam halo, and electron cloud. We also present an overview of systems more specifically tailored to address these problems, including Beam-in-Gap measurement and cleaning, two types of incoherent tune measurement, halo monitor, and video monitors for stripping foils and the electron catcher.