Systems and methods for integrated circuits comprising multiple body biasing domains. In accordance with a first embodiment of the present invention, a semiconductor structure comprises a substrate of first type material. A first closed structure comprising walls of second type material extends from a surface of the substrate to a first depth. A planar deep well of said second type material underlying and coupled to the closed structure extends from the first depth to a second depth. The closed structure and the planar deep well of said second type material form an electrically isolated region of the first type material. A second-type semiconductor device is disposed to receive a first body biasing voltage from the electrically isolated region of the first type material. A well of the second-type material within the electrically isolated region of the first type material is formed and a first-type semiconductor device is disposed to receive a second body biasing voltage from the well of second-type material.