Techniques are developed for studying the mechanism of localized corrosion and protective measures against such corrosion are suggested. The pH values and composition of the occluded solution at different propagation stages are determined. Measurements of the critical pH value and corrosion rate inside the occluded cells are conducted. Potential-pH diagrams depicting kinetic and thermodynamic behaviors of occluded cell corrosion are being established. The mechanism of inhibition of pitting and stress corrosion cracking have also been investigated.