An asymmetric volume booster assembly comprising: an actuator (24, 500) movable in a first direction and a second direction; a main fluid supply line (52, 520); a valve positioner (56, 514) in flow communication with the main fluid supply line and arranged to supply first and second signals; a first volume booster in flow communication with a first side of the actuator and in flow communication with the main fluid supply line via a first booster supply line, the first volume booster defining both a supply passage (104, 110) and an exhaust passage (104, 126, 128, 142, 144, 146, 148), the supply passage arranged to route fluid to the first side of the actuator to move the actuator in the first direction in response to the first signal received from the valve positioner; and a second volume booster in flow communication with a second side of the actuator and in flow communication with the main fluid supply line via a second booster supply line, the second volume booster defining both a supply passage (110, 204, 206, 102, 108) and an exhaust passage (204, 226, 224), the supply passage arranged to route fluid to the second side of the actuator to move the actuator in the second direction in response to the second signal received from the valve positioner; characterized in that: the first and second volume boosters are functionally asymmetrical relative to one another, and wherein the functional asymmetry is achieved by at least one of: a) first resistance to flow of exhaust through the exhaust passage of the first volume booster being less than a second resistance to flow of exhaust through the exhaust passage of the second volume booster; or b) a first resistance to fluid flow through the supply passage of the first volume booster being greater than a second resistance to fluid flow through the supply passage of the second volume booster; and further comprising a first line from the positioner to the first booster and a second line from the positioner to the second booster, wherein the positioner selectively signals the first and second boosters with pressurized fluid through the first and second lines, with the first and second signals, respectively, wherein the asymmetric volume booster assembly is arranged such that the delivery of the first signal is slower than the delivery of the second signal. an actuator (24, 500) movable in a first direction and a second direction; a main fluid supply line (52, 520); a valve positioner (56, 514) in flow communication with the main fluid supply line and arranged to supply first and second signals; a first volume booster in flow communication with a first side of the actuator and in flow communication with the main fluid supply line via a first booster supply line, the first volume booster defining both a supply passage (104, 110) and an exhaust passage (104, 126, 128, 142, 144, 146, 148), the supply passage arranged to route fluid to the first side of the actuator to move the actuator in the first direction in response to the first signal received from the valve positioner; and a second volume booster in flow communication with a second side of the actuator and in flow communication with the main fluid supply line via a second booster supply line, the second volume booster defining both a supply passage (110, 204, 206, 102, 108) and an exhaust passage (204, 226, 224), the supply passage arranged to route fluid to the second side of the actuator to move the actuator in the second direction in response to the second signal received from the valve positioner; characterized in that: the first and second volume boosters are functionally asymmetrical relative to one another, and wherein the functional asymmetry is achieved by at least one of: a) first resistance to flow of exhaust through the exhaust passage of the first volume booster being less than a second resistance to flow of exhaust through the exhaust passage of the second volume booster; or b) a first resistance to fluid flow through the supply passage of the first volume booster being greater than a second resistance to fluid flow through the supply passage of the second volume booster; and further comprising a first line from the positioner to the first booster and a second line from the positioner to the second booster, wherein the positioner selectively signals the first and second boosters with pressurized fluid through the first and second lines, with the first and second signals, respectively, wherein the asymmetric volume booster assembly is arranged such that the delivery of the first signal is slower than the delivery of the second signal. a) first resistance to flow of exhaust through the exhaust passage of the first volume booster being less than a second resistance to flow of exhaust through the exhaust passage of the second volume booster; or b) a first resistance to fluid flow through the supply passage of the first volume booster being greater than a second resistance to fluid flow through the supply passage of the second volume booster; and further comprising a first line from the positioner to the first booster and a second line from the positioner to the second booster, wherein the positioner selectively signals the first and second boosters with pressurized fluid through the first and second lines, with the first and