Supported cobalt catalysts are preferred for the Fischer-Tropsch Synthesis (FTS) in Gas-to-Liquid (GTL) plants. Cobalt is a relatively expensive metal, so catalyst lifetime is crucial to the economics of the process. There are clear advantages in using the regeneration of an aged FTS catalyst as a catalyst management tool. Oxidative regeneration of spent cobalt catalysts has been the most favored method in both open and patent literature. Aspects of the oxidation and reduction steps of the regeneration process have been investigated from a fundamental point of view, using both model and realistic catalyst systems. This understanding provided insights into the practical application of regeneration where it is shown that multiple regeneration cycles of the aged catalyst can be performed successfully on the demonstration scale.