An actuation apparatus for actuating one or more components of a respective one or more switchable valve train devices of a first group of switchable valve train devices, and for actuating one or more components of a respective one or more switchable valve train devices of a second group of switchable valve train devices, the actuation apparatus including: a body rotatable by an actuation source about a rotation axis; a first shaft including a first set of one or more levers for actuating the one or more components of the first group of switchable valve train devices, the first shaft including a first element for contacting the body and moveable by the body in use to cause the first shaft to rotate; and a second shaft including a second set of one or more levers for actuating the one or more components of the second group.