A fuel pump comprising: a housing ; an inlet port for receiving low pressure feed fuel; a pumping chamber within the housing for pressurizing the feed fuel; an outlet port for discharging the feed fuel after pressurization; a fuel delivery module mounted in the housing, including an inflow passage for receiving feed fuel from the inlet port, a delivery passage for delivering feed fuel to the pumping chamber, a valve seat between the inflow passage and the delivery passage , and a valve member movable between a first position against the seat whereby the valve member closes fuel flow to the delivery passage and a second position away from the seat whereby the valve member retracts from the seat to open fuel flow to the delivery passage ; an actuation module attached to at least one of the delivery module and housing , including an electromagnetic coil assembly that is operatively associated with the valve member for moving the valve member between the first and second positions; wherein the actuation module is hydraulically isolated from the fuel delivery module , characterized in that the delivery module is internal to the housing and has a lower portion that is hydraulically sealed against the housing; the actuation module is attached to the lower portion of the delivery module and projects entirely external to the housing ; the actuation module has a first magnetic pole , a surrounding coil , and a magnetically conductive outer jacket ; the lower portion of the delivery module defines a second magnetic pole magnetically coupled to the first magnetic pole and includes said valve seat ; the valve member is ferromagnetic; and the valve member has a sealing face directly magnetically coupled to the electromagnetic coil through the first and second magnetic poles , whereby the coil is selectively energizable to generate a magnetic flux path directly through the sealing face of the valve member and a sealing surface of the seat . a housing ; an inlet port for receiving low pressure feed fuel; a pumping chamber within the housing for pressurizing the feed fuel; an outlet port for discharging the feed fuel after pressurization; a fuel delivery module mounted in the housing, including an inflow passage for receiving feed fuel from the inlet port, a delivery passage for delivering feed fuel to the pumping chamber, a valve seat between the inflow passage and the delivery passage , and a valve member movable between a first position against the seat whereby the valve member closes fuel flow to the delivery passage and a second position away from the seat whereby the valve member retracts from the seat to open fuel flow to the delivery passage ; an actuation module attached to at least one of the delivery module and housing , including an electromagnetic coil assembly that is operatively associated with the valve member for moving the valve member between the first and second positions; wherein the actuation module is hydraulically isolated from the fuel delivery module , characterized in that the delivery module is internal to the housing and has a lower portion that is hydraulically sealed against the housing; the actuation module is attached to the lower portion of the delivery module and projects entirely external to the housing ; the actuation module has a first magnetic pole , a surrounding coil , and a magnetically conductive outer jacket ; the lower portion of the delivery module defines a second magnetic pole magnetically coupled to the first magnetic pole and includes said valve seat ; the valve member is ferromagnetic; and the valve member has a sealing face directly magnetically coupled to the electromagnetic coil through the first and second magnetic poles , whereby the coil is selectively energizable to generate a magnetic flux path directly through the sealing face of the valve member and a sealing surface of the seat . <EOS>