An apparatus 7 for moving a valve(s) 27a for a combustion chamber 5 of an internal combustion engine 3 comprises a first piston 23a within a first chamber 25a, configured to actuate a first valve 27a for the combustion chamber. The first piston is arranged to be actuated by a hydraulic control system 21 to move within the first chamber 25a, for moving the first valve and a second piston 23b within a second chamber 25b is configured to not actuate any valve for any combustion chamber. The hydraulic control system is arranged to, in a first mode, control actuation of the first piston but not the second piston and, in a second mode, control parallel actuation of the pistons. Preferably in the second mode the pistons are actuated simultaneously. The apparatus may comprise a blocking means (33b, 33d, figure 3), operable in the first mode. The second piston may comprise a resilient means (29a-c) to resist actuation as may any further pistons. The second or further pistons may comprise a limiter. An internal combustion engine, a valve train, a vehicle, a system and a method are also claimed.
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