A valve assembly for a fuel injector (16, fig 1) for delivering fuel to an internal combustion engine comprises an armature assembly with an armature 62 movable within a fluid chamber (35, fig 8) of the fuel injector under the influence of an actuation force. The armature has a front surface 68 and a rear surface 69 and defines at least one flow path 82 to allow a flow of fluid through the armature between the front and rear surfaces, and at least one valve element (76, fig 7) mounted at the rear surface. The or each valve element is operable under the influence of fluid pressure to allow the flow of fluid through the at least one flow path and around the fluid chamber, thereby balancing fluid pressure at the front and rear surfaces to minimise fluctuations in movement. A fuel injector comprising the valve assembly has an electromagnetic actuator (34, fig 1) for applying an electromagnetic force to the armature.
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