A fluid-filled soft prosthetic implant having a shell with a reinforced shell wall. The soft prosthetic implant may be for breast reconstruction or augmentation, or to restore the normal appearance of soft tissue in the buttocks, chin, calf, etc. The implants may be reinforced using several methods: reinforcement of the shell wall, non-homogeneous gel-filling, or both. At least a portion of the perimeter region desirably has a shell wall thickness greater than the average shell wall thickness of either the anterior face or the posterior face. The added material at the perimeter region strengthens that area in which a large percentage of implant ruptures occur. The reinforced perimeter also helps to prevent the implant from collapsing or folding, which can cause undesirable rippling or wrinkling visible through the patient's skin. The remainder of the shell will desirably have a nominal wall thickness to retain the overall softness and supple feel of the implant. The implant shell may be filled with gels of different gel cohesiveness to counterbalance any reinforced area or to provide added reinforcement.