A rocker arm for a valve train assembly includes: a first body; a second body mounted for pivotal movement with respect to the first body; and a latching arrangement. The latching arrangement includes a latch pin drivable in response to an external actuator from a first position in which the first body and the second body are un-latched to a second position in which the latch pin latches the first body and the second body together. The latching arrangement includes a piston member and a first biasing member. The piston member is arranged such that if the external actuator attempts to cause the latch pin to be driven from the first position to the second position at a time when the latch pin is prevented from being driven, the piston member moves to bias the biasing member so that the biasing member urges the latch pin to the second position.