Deactivation pathways for supported cobalt catalysts in Fischer-Tropsch (FT) synthesis have been found to comprise a number of independent mechanisms. The degree to which the various mechanisms apply is expected to be specific to each particular catalyst formulation and operating condition. The highest activity FT catalysts, finding industrial application, are used in microchannel reactors. Such catalysts provide a useful benchmark for FT catalyst performance comparisons. Deactivation mechanisms are grouped according to the methods used to manage them for typical industrial applications and then quantified to provide for the proposed benchmark catalyst behaviour.