A side actuated collet lock mechanism includes a collet; a drawbar at least partially disposed within the collet, and a pair of wedge members threadingly received onto each end of a double-ended drive screw. The drive screw is rotated to cause the wedge members to move downward such that a first cam surface engages the drawbar. The drawbar and collet are pulled into the tool holder and firmly secure the shank. To remove the shank, the drive screw is rotated in an opposite direction to cause the wedge members to move upward such that a second cam surface engages the drawbar. The drawbar and the collet are pushed out from the toolholder, thereby releasing the shank.