A surgical stapler including a tool assembly having a pair of opposing tissue engaging surfaces (110, 120) for deforming a plurality of surgical fasteners through and fastening tissue, the tool assembly being attached at a distal end of the surgical stapler, the surgical stapler comprising: a housing having a fixed handle; a drive assembly including a coupling member operatively coupled to a shaft connector which is coupled to a firing shaft, such that longitudinal movement of the coupling member in the direction "D" is translated to the firing shaft to advance a stapling firing mechanism, the coupling member including a rack surface and a ratchet track having one or more teeth, said ratchet track interfacing with a pawl allowing for unidirectional motion; a moveable handle, selectively movable relative to said fixed handle from a first position in spaced relation relative to said fixed handle to a second position closer to said fixed handle to manually effect both the clamping of tissue and the deployment and deformation of staple fasteners via the coupling member, said moveable handle being mounted to said housing and rotatively coupled to pawl so as to engage one of the teeth of ratchet track when the moveable handle is moved to the second position to advance coupling member in the distal direction "D" to actuate the clamping of tissue and the deployment and deformation of fasteners; wherein the drive assembly includes a power source and a motor which engages the coupling member, the coupling member being operatively coupled to the moveable handle, wherein movement of the movable handle to a third position activates the motor, the motor being arranged with the coupling member, via the track surface, so that activation of the motor advances the coupling member which in turn advances a firing shaft to deploy and deform the surgical fasteners, the drive assembly including a controller, such that the rate at which the motor advances the coupling member is variably controlled in response to the force exerted on the movable handle during movement thereof to the third position. a housing having a fixed handle; a drive assembly including a coupling member operatively coupled to a shaft connector which is coupled to a firing shaft, such that longitudinal movement of the coupling member in the direction "D" is translated to the firing shaft to advance a stapling firing mechanism, the coupling member including a rack surface and a ratchet track having one or more teeth, said ratchet track interfacing with a pawl allowing for unidirectional motion; a moveable handle, selectively movable relative to said fixed handle from a first position in spaced relation relative to said fixed handle to a second position closer to said fixed handle to manually effect both the clamping of tissue and the deployment and deformation of staple fasteners via the coupling member, said moveable handle being mounted to said housing and rotatively coupled to pawl so as to engage one of the teeth of ratchet track when the moveable handle is moved to the second position to advance coupling member in the distal direction "D" to actuate the clamping of tissue and the deployment and deformation of fasteners; wherein the drive assembly includes a power source and a motor which engages the coupling member, the coupling member being operatively coupled to the moveable handle, wherein movement of the movable handle to a third position activates the motor, the motor being arranged with the coupling member, via the track surface, so that activation of the motor advances the coupling member which in turn advances a firing shaft to deploy and deform the surgical fasteners, the drive assembly including a controller, such that the rate at which the motor advances the coupling member is variably controlled in response to the force exerted on the movable handle during movement thereof to the third position.