A surgical retractor system, comprising: a substantially rigid frame defining a plane, a plurality of arms (120, 122) connected to the frame, each arm (120, 122) having a longitudinal axis extending from a proximal end to a distal end of said arm (120, 122), wherein at least one arm is moveable relative to the frame, and wherein the relative movement is constrained to a direction along the longitudinal axis of the arm, retractor blades removably connected to each of the plurality of arms (120, 122) adjacent the distal end, the blade extending generally perpendicular to the longitudinal axis and being fixably rotatable about an axis normal to the longitudinal axis of the arm (120, 122) to which it is connected; a bar clamp mechanism connected to the frame and associated with at least one moveable arm to releasably clamp the arm in a fixed position relative to the frame, and wherein each moveable arm is non-threadedly connected to the frame and is actuatable by a manual retraction tool; characterized in that said frame further comprises a slot adapted to engage a part of said manual retraction tool, the system being configured such that when another part of retraction tool is adjacent to an inner portion of said retraction blade, the squeezing of a handle of the tool causes the retraction of the blade in an outward direction; and wherein the bar clamp mechanism includes a latch member and a spring, the latch member being adapted to be biased by the spring against said arm so that said bar clamp mechanism allows infinite adjustment and holds said arm at a precise expanded position in order to prevent inadvertent inward movement of said arm once it has been retracted outward. a substantially rigid frame defining a plane, a plurality of arms (120, 122) connected to the frame, each arm (120, 122) having a longitudinal axis extending from a proximal end to a distal end of said arm (120, 122), wherein at least one arm is moveable relative to the frame, and wherein the relative movement is constrained to a direction along the longitudinal axis of the arm, retractor blades removably connected to each of the plurality of arms (120, 122) adjacent the distal end, the blade extending generally perpendicular to the longitudinal axis and being fixably rotatable about an axis normal to the longitudinal axis of the arm (120, 122) to which it is connected; a bar clamp mechanism connected to the frame and associated with at least one moveable arm to releasably clamp the arm in a fixed position relative to the frame, and wherein each moveable arm is non-threadedly connected to the frame and is actuatable by a manual retraction tool; characterized in that said frame further comprises a slot adapted to engage a part of said manual retraction tool, the system being configured such that when another part of retraction tool is adjacent to an inner portion of said retraction blade, the squeezing of a handle of the tool causes the retraction of the blade in an outward direction; and wherein the bar clamp mechanism includes a latch member and a spring, the latch member being adapted to be biased by the spring against said arm so that said bar clamp mechanism allows infinite adjustment and holds said arm at a precise expanded position in order to prevent inadvertent inward movement of said arm once it has been retracted outward.