A valve bridge system for use with an engine valve assembly of an internal combustion engine, the engine valve assembly comprising at least two engine valves, at least two valve springs (208, 210) corresponding to the at least two engine valves and at least two spring retainers (209, 211) corresponding to the at least two engine valves, the valve bridge system comprising: a valve bridge (204, 212) configured to extend between the at least two engine valves; and a valve bridge guide (206, 502, 702, 902, 1102, 1202, 1302) operatively connected to the valve bridge and comprising a valve bridge control surface configured to selectively contact at least one of the valve bridge or the engine valve assembly, wherein the valve bridge guide is configured to extend downward between the at least two valve springs, characterised in that the valve bridge control surface is at least one concave surface corresponding to at least one convex surface defined by the at least two valve springs or the at least two spring retainers, wherein the valve bridge control surface is configured to be as close as possible to one or more of the at least two valve springs or the at least two spring retainers such that normal movement and vibration of the valve bridge, valve bridge guide and at least two valve springs does not result in contact between the valve bridge control surface and the springs or spring retainers of the engine valve assembly when the valve bridge is in a controlled state relative to the at least two engine valves, and wherein the valve bridge control surface is configured to contact the at least one of the springs or spring retainers of the engine valve assembly to resist uncontrolled movement of the valve bridge when the valve bridge is in an uncontrolled state relative to the at least two engine valves. a valve bridge (204, 212) configured to extend between the at least two engine valves; and a valve bridge guide (206, 502, 702, 902, 1102, 1202, 1302) operatively connected to the valve bridge and comprising a valve bridge control surface configured to selectively contact at least one of the valve bridge or the engine valve assembly, wherein the valve bridge guide is configured to extend downward between the at least two valve springs, characterised in that the valve bridge control surface is at least one concave surface corresponding to at least one convex surface defined by the at least two valve springs or the at least two spring retainers, wherein the valve bridge control surface is configured to be as close as possible to one or more of the at least two valve springs or the at least two spring retainers such that normal movement and vibration of the valve bridge, valve bridge guide and at least two valve springs does not result in contact between the valve bridge control surface and the springs or spring retainers of the engine valve assembly when the valve bridge is in a controlled state relative to the at least two engine valves, and wherein the valve bridge control surface is configured to contact the at least one of the springs or spring retainers of the engine valve assembly to resist uncontrolled movement of the valve bridge when the valve bridge is in an uncontrolled state relative to the at least two engine valves.