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In  the  automotive  industry  many  high  strength  steel  fasteners  are  zinc electroplated.  The  plating  process  is  thought  to  be  a  principal  cause  of  hydrogen embrittlement: fasteners can fail unpredictably at  applied stress levels well below the fracture  stress.  To  avoid  this  a  hydrogen  relief  heat  treatment  after  electroplating  is commonly applied. In this study the effect of plating and post-plating treatments on the slow strain rate tensile fracture behaviour of two commercial steels has been investigated. Testing  was  conducted  on  fatigue  pre-cracked  cylindrical  specimens  in  air.  Results describing the effect of  alloy selection,  metallurgical  processing conditions  and  heat treatment on the susceptibility to  hydrogen  embrittlement  are presented. The principal conclusion  drawn  from  this  study  is  that  post-plating  hydrogen  relief  annealing,  as specified by international standards, is not always of benefit.