New wet flue gas desulfurization (WFGD) units fabricated from duplex stainless steel are experiencing premature localized corrosion at coal burning power plants. Corrosion rates in excess of 500 mils per have been observed in several absorbers. A root cause analysis was performed to determine the contributing factors that resulted in the rapid initiation and propagation of localized corrosion on duplex stainless steel UNS S32205. The root-cause analysis consisted of collecting forensic data from the field reviewing the existing literature and conducting laboratory and field experiments. Employees of utility plants and WFGD subject-matter experts were interviewed in order to obtain additional field data from more than 30 individual absorbers. The most significant finding of the root-cause analysis was that 2205 duplex stainless steel is susceptible to localized corrosion in WFGD service. Other contributing factors included the presence of scale that acted as a crevice former manganese rich deposits on the absorber walls and detrimental surface preparation.