Based on icrp, ncrp, and frc guides for protection of individuals and the public against exposure to ionizing radiation, the aec necessarily has issued (and occasionally updates) its general regulations applicable to activities in this area, including nuclear power reactors. These are known as its “Standards for Protection against Radiation” (10 CFR Pt. 20). When it is desired to con­struct and operate a nuclear reactor, the Commission’s “Licensing Production and Utilization Facilities” regulations (10 CFR Pt. 36) come into play as a means of applying the general regulations to a specific reactor at a specific site. There follows a description of the latter process and a discussion of the isolation of regulatory and licensing responsibilities within the aec.