A foam pump includes a fluid cylinder, an air cylinder, and a mixing chamber, in which the fluid cylinder is adapted to draw a fluid therein in a priming stroke, and to pump the fluid into the mixing chamber in a dispensing stroke, in which the air cylinder is adapted to draw air therein in a priming stroke, and to pump the air into the mixing chamber in a dispensing stroke, in which the mixing chamber includes a fluid throughflow axis, in which the fluid cylinder and the air cylinder are co-axial with one another and are aligned on a second axis which is substantially normal to the fluid throughflow axis, in which the fluid cylinder and the air cylinder are provided with a common piston member, and in which the foam pump includes spring means adapted to bias the common piston member to perform a priming stroke of the fluid cylinder and the air cylinder.