A pump comprising: a pump body having a substantially cylindrical shape defining a cavity for containing a fluid, the cavity being formed by a side wall closed at both ends by end walls (12,13), at least one of the end walls being a driven end wall having a central portion and a peripheral portion extending radially outwardly from the central portion of the driven end wall; an actuator operatively associated with the central portion of the driven end wall to cause an oscillatory motion of the driven end wall, thereby generating displacement oscillations of the driven end wall in a direction substantially perpendicular thereto with an annular node between the centre of the driven end wall and the side wall when in use; a first aperture disposed at any location in the cavity other than at the location of the annular node and extending through the pump body; a second aperture disposed at any location in the pump body other than the location of said first aperture and extending through the pump body; and, a flap valve disposed in at least one of said first aperture and second aperture; whereby the displacement oscillations generate corresponding radial pressure oscillations of the fluid within the cavity of said pump body causing fluid flow through said first and second apertures when in use; characterized by an isolator operatively associated with the peripheral portion of the driven end wall to reduce dampening of the displacement oscillations; and in that said flap valve comprises: a first plate having apertures extending generally perpendicular through said first plate; a second plate having first apertures extending generally perpendicular through said second plate, the first apertures being substantially offset from the apertures of said first plate; a spacer disposed between said first plate and said second plate to form a cavity therebetween in fluid communication with the apertures of said first plate and the first apertures of said second plate; and, a flap disposed and moveable between said first plate and said second plate, said flap having apertures substantially offset from the apertures of said first plate and substantially aligned with the first apertures of said second plate; whereby said flap is motivated between said first and second plates in response to a change in direction of the differential pressure of the fluid across said flap valve. a pump body having a substantially cylindrical shape defining a cavity for containing a fluid, the cavity being formed by a side wall closed at both ends by end walls (12,13), at least one of the end walls being a driven end wall having a central portion and a peripheral portion extending radially outwardly from the central portion of the driven end wall; an actuator operatively associated with the central portion of the driven end wall to cause an oscillatory motion of the driven end wall, thereby generating displacement oscillations of the driven end wall in a direction substantially perpendicular thereto with an annular node between the centre of the driven end wall and the side wall when in use; a first aperture disposed at any location in the cavity other than at the location of the annular node and extending through the pump body; a second aperture disposed at any location in the pump body other than the location of said first aperture and extending through the pump body; and, a flap valve disposed in at least one of said first aperture and second aperture; whereby the displacement oscillations generate corresponding radial pressure oscillations of the fluid within the cavity of said pump body causing fluid flow through said first and second apertures when in use; characterized by an isolator operatively associated with the peripheral portion of the driven end wall to reduce dampening of the displacement oscillations; and in that said flap valve comprises: a first plate having apertures extending generally perpendicular through said first plate; a second plate having first apertures extending generally perpendicular through said second plate, the first apertures being substantially offset from the apertures of said first plate; a spacer disposed between said first plate and said second plate to form a cavity therebetween in fluid communication with the apertures of said first plate and the first apertures of said second plate; and, a flap disposed and moveable between said first plate and said second plate, said flap having apertures substantially offset from the apertures of said first plate and substantially aligned with the first apertures of said second plate; whereby said flap is motivated between said first and second plates in response to a change in direction of the differential pressure of the fluid across said flap valve. a first plate having apertures extending generally perpendicular through said first plate; a second plate having first apertures extending generally perpendicular through said second plate, the first apertures being substantially offset from the apertures of said first plate; a spacer disposed between said first plate and said second plate to form a cavity therebetween in fluid communication with the apertures of said first plate and the first apertures of said second plate; and, a flap disposed and moveable between said first plate and said second plate, said flap having apertures substantially offset from the apertures of said first plate and substantially aligned with the first apertures of said second plate; whereby said flap is motivated between said first and second plates in response to a change in direction of the differential pressure of the fluid across said flap valve.