This chapter describes issues related to corrosion of carbon steel weldments and remedial measures that have proven successful in specific cases. The forms of corrosion covered includes preferential heat affected zone corrosion, preferential weld metal corrosion, and galvanic corrosion. Industrial case studies demonstrating the necessity for testing each galvanic couple in the environment for which it is intended are presented. The chapter also discusses various factors associated with stress-corrosion cracking in oil refineries.