The purpose of this technical committee report is to present state of the art information on corrosion inhibiting admixtures. It is intended to provide specifiers, designers, and corrosion control personnel information to control the corrosion of conventional reinforcing steel in hydraulic cement concrete using corrosion inhibiting admixtures.This report describes several types of materials used as corrosion inhibiting admixtures, their selection and evaluation, their proportioning into freshly mixed concrete, and their effects on fresh and hardening/hardened concrete. Corrosion inhibiting admixtures may help delay corrosion initiation and extend the interval of corrosion propagation. However, the corrosion of reinforcing steel in concrete depends on factors beyond the presence of corrosion inhibiting admixtures, including the service environment, the quality of the concrete, the environmental exposure of the structure, the formation and presence of cracks, the cover of the reinforcing steel, and other factors. This report covers only admixed corrosion inhibitors used in reinforced concrete. Migrating corrosion inhibitors applied on hardened concrete and other corrosion inhibiting substances are beyond the scope of this document.