This standard covers the proper design and construction of concrete structures that form part of a nuclear power plant and that have nuclear safety-related functions, but does not cover concrete reactor vessels and concrete containment structures (as defined by Joint ACI-ASME Committee 359). The structures covered by the Code include concrete structures inside and outside the containment system. This Code may be referenced and applied subject to agreement between the owner and the Regulatory Authority. All notation sections have been removed from the beginning of each chapter and consolidated into one list in Chapter 2. The format of this Code is based on the “Building Code Requirements for Structural Concrete (ACI 318-05)” and incorporates recent revisions of that standard. The commentary, which is presented after the Code, discusses some of the considerations of ACI Committee 349 in developing “Code Requirements for Nuclear Safety-Related Concrete Structures (ACI 349-06).” This information is provided in the commentary because the Code is written as a legal document and therefore cannot present background details or suggestions for carrying out its requirements.