A variable cohesive gel form stabilizing implant is disclosed for augmentation or reconstruction of the breast. The prosthesis of this invention comprises an implantable shell or envelope (not limited to a single shell or envelope), filled with a biocompatible gel, or gels, having alterations in gel cohesiveness to maintain stable form, shape, and dimension after surgical implantation. The gel cohesiveness may increase, with increased volume or dimension of the prosthesis. The variable cohesiveness of the gel filler material may be altered by any means (i.e. chemical, fabrication, etc.). The variable cohesive gel form stabilizing implant has shape retention characteristics to maintain its form, thereby reducing or eliminating the undesirable effects of shell wrinkling, knuckling, scalloping or deformation, which can occur at the upper or lower pole of the prostheses, along the perimeter of the shell or at the base, post-implantation. Finally, the variable cohesive gel form stabilizing implant provides new control and possibilities for achieving and preserving the most natural breast shape.