A light weight printed wiring board that is particularly well suited for high-G and/or other weight sensitive applications is provided. In one illustrative embodiment, a light weight PWB is provided that includes a substrate having one or more layers extending generally parallel to a plane. To help reduce the weight of the PWB, the substrate may have or define one or more lighter weight regions. In some cases, the one or more lighter weight regions may consume greater than 25%, 30%, 40%, 50%, 60%, 75% or more of the overall volume of the substrate, and thus the weight of the substrate may be reduced by greater than 25%, 30%, 40%, 50%, 60%, 75% or more.