This paper discusses the process used to develop an environmental health addendum to the Assessment Protocol for Public Health (APEX/PH). Local health departments in Washington State are undertaking a trial program utilizing APEX/PH. The environmental health addendum was developed in response to the paucity of environmental health-oriented data requested in APEX/PH, Part II, the Community Process, and includes environmental exposure indicators as well as health status indicators. The methods used to gain a consensus among key environmental health professionals in Washington State are discussed and an environmental issue prioritization scheme is recommended. The need for the environmental health addendum and future work on the addendum and APEX/PH are discussed.