To represent the battle standard's steadying presence, friendly models within 12" of the Battle Standard Bearer re-roll failed Leadership tests of any kind, including Panic tests, Break tests, Fear tests, Rally tests and so on. This ability cannot be used if the Battle Standard Bearer is himself fleeing – no one takes heart from the sight of a coward. With this in mind, it's always best to attempt to rally your Battle Standard Bearer before you take other Rally tests, if you can.