On August 9, 1997 staff at the Monterey Regional Water Pollution Control Agency's (MRWPCA or Agency) Regional Wastewater Treatment Plant (RTP) moved into a newly constructed administration building. With occupancy of this new building, MRWPCA became the first commercial, industrial, and/or governmental agency in the region with a dual-plumbing system to supply recycled water to non-potable interior plumbing fixtures. This paper will focus on the intergovernmental coordination necessary to win approval of this project. The objectives of this paper are to: provide a general overview of the dual plumbing system and highlight some of the unique physical features of the system and discuss other recycled water uses at the RTP; discuss the planning process and intergovernmental coordination issues and public policy issues related to interior use of recycled water; describe the testing requirements and restrictions required by local regulatory agencies; and, briefly discuss future trends related to indoor use of recycled water. Includes 4 references.