Abstract: An insert for a shoe comprises a pouch having a moldable, thixotropic material and a shell having a catalyst. The shell is capable of being ruptured by massaging the pouch to allow the catalyst to be released from the shell and mixed with the material. A pressure sensitive adhesive is on the bottom of the pouch to secure it to the inner sole of a shoe, and a nylon layer is on the top of the pouch to absorb moisture and provide an aesthetic appearance. In use, the pouch is massaged to mix the catalyst and moldable material and is then placed in a shoe. The user places a foot in the shoe and applies a light weight to the foot so that the pouch assumes the shape of the foot bottom and fills that space between the foot and the shoe. Then, the foot is removed to allow the material to cure. When the material is cured the insert prevents excessive collapse of the foot.