The FIH trialled the one-on-one shootout method (as opposed to "from-the-spot" shots) in the 2010 Champions Trophy and Champions Challenge as well as the Azlan Shah playoffs on the 15th May 2011.
These trials were to see if it was a suitable alternative to put in place for the 2012 London Olympics.
In the shoot-out, the striker starts the one-on-one attack against the goalkeeper from 23 yards. The striker has eight seconds to enter the striking circle and score. He is allowed to flick, push, drive or dribble past the custodian, who can come off the goalline to try and deny him a goal.
Like the penalty-strokes tie-breaker, if the deadlock persists after the five mandatory attempts by each team, the shoot-out will go into sudden-death.
Following the successful trials, the FIH has adopted this rule for all classification fixtures.
See this briefing which has more detail.