A system for custom fitting shoes comprising: (a) an adjustable footform last for custom fitting footwear having medial and lateral sides, and an instep area, and adapted to be inserted into a shoe with an upper constructed at least in part of treatable material in activation zones, said last comprising: a last body; a medial adjustment element extending along a portion of the medial side of said last body, said medial adjustment element being movable toward and away from said last body; a lateral adjustment element extending along a portion of the lateral side of said last body, said lateral adjustment element being movable toward and away from said last body; and a calibration mechanism cooperatively coupled to an adjustment mechanism to move either of said medial adjustment element and said lateral adjustment element; and (b) an activation chamber adapted to receive and treat the shoe fitted onto said adjustable last until the activation zones are plastic and to set the treatable material to fix the width of the shoe, wherein said activation chamber is an infrared activation chamber comprising a plurality of infrared lamps (52a, 52b, 52c) positioned around a target area, wherein a detent is present on the footform last and arranged to position the footform last with respect to the activation chamber, and wherein said activation chamber comprises a safeguard preventing activation of the chamber without an appropriately designed shoe positioned in the target area, wherein said safeguard is the detent on said adjustable last and a mating switch on said chamber. (a) an adjustable footform last for custom fitting footwear having medial and lateral sides, and an instep area, and adapted to be inserted into a shoe with an upper constructed at least in part of treatable material in activation zones, said last comprising: a last body; a medial adjustment element extending along a portion of the medial side of said last body, said medial adjustment element being movable toward and away from said last body; a lateral adjustment element extending along a portion of the lateral side of said last body, said lateral adjustment element being movable toward and away from said last body; and a calibration mechanism cooperatively coupled to an adjustment mechanism to move either of said medial adjustment element and said lateral adjustment element; and a last body; a medial adjustment element extending along a portion of the medial side of said last body, said medial adjustment element being movable toward and away from said last body; a lateral adjustment element extending along a portion of the lateral side of said last body, said lateral adjustment element being movable toward and away from said last body; and a calibration mechanism cooperatively coupled to an adjustment mechanism to move either of said medial adjustment element and said lateral adjustment element; and (b) an activation chamber adapted to receive and treat the shoe fitted onto said adjustable last until the activation zones are plastic and to set the treatable material to fix the width of the shoe, wherein said activation chamber is an infrared activation chamber comprising a plurality of infrared lamps (52a, 52b, 52c) positioned around a target area,