The National Environmental Policy Act (NEPA) is the basic national charter that establishes policy, sets goals, and provides a framework for comprehensive environmental planning. NEPA directs federal agencies to undertake an integrated environmental planning process that encompasses the totality of environmental resources. The NEPA process contains “action-forcing” mechanisms that prompt agencies to consult with other agencies possessing specialized expertise or regulatory jurisdiction over a potentially affected resource. Many of these consultations satisfy specific regulatory requirements through resource-specific regulations such as Section 7 of the Endangered Species Act and Section 106 of the National Historic Preservation Act. The case studies presented within this article are used to demonstrate a 9-step integrated process for integrating regulatory agency consultations and supporting studies with the completion of an Environmental Assessment (EA) or an Environmental Impact Statement (EIS). The three case studies (Case Study 1, a Supplemental EIS for the Meramec Regional Wastewater Treatment Plant; Case Study 2, an EA for a variety of water infrastructure improvement projects; and Case Study 3, an EA for the placement of an undersea cable within a National Marine Sanctuary) illustrate how regulatory agency consultations can be integrated into the NEPA process using this 9-step method. Implementation of the method ensures that (1) adequate planning, crucial project decisions, and environmental considerations are identified; (2) the chance of potential conflicts with regulatory agencies because of inadequate regulatory considerations is reduced; (3) timely and costly delays in the completion of the NEPA process are avoided; and (4) the NEPA process is streamlined to produce a legally defensible and comprehensive NEPA document.