We present evidence of the following. 1. Modern silicone bag-gel breast implants leak silicone gel through the bag. 2. The amount of silicone leaked by an intact implant varies from one implant to another, and is not constant for any type or brand. 3. The leaked silicone, together with fibrous thickening and various degrees of inflammation will be found in capsules surrounding the implants if extensive biopsies are taken and many sections are examined.