High Voltage Direct Current (HVDC) converter stations represent a significant investment and source of revenue for the electric utilities owning them. Many installations are approaching or exceeding thirty (30) years of service. Components are aging. Manufacturers may no longer be in business or have merged and consolidated their resources with different business priorities. Engineering and technical staffs are retiring and the knowledge base is being lost. Technology is advancing making existing technology obsolete or so dated it no longer functions efficiently. AEP (American Electric Power) has worked with EPRI (Electric Power Research Institute) and investigated the life extension of Oklaunion Converter Station (OCS). This paper is intended to discuss the investigation methods and the results of that investigation of the equipment, subassemblies, and subsystems within OCS selected by AEP. It will also give utilities contemplating such an investigation a life extension strategy for their facilities.