The Montgomery County Department of Parks, and other environmentally-oriented organizations, have historically had a difficult time communicating the importance of environmental issues to the general public. A major reason is that much of this communication has promoted environmental protection for the intrinsic sake of the environment, and not for human well-being. As a result, people who are not already environmentally inclined may not be interested in protecting it; they are unaware of how environmental crises may impact their own well-being. If they were made aware of such impacts, they might be more invested in environmental protection. To address this issue, we investigated the connections between environmental and human health, and determined how those connections should be crafted and messaged, to initiate a call to pro-environmental action among diverse groups in the Montgomery County public. We carried these tasks out in the context of a park system and focused our work on how parks are beneficial to both human and environmental health, and how they can be used to message human-environment connections and pro-environmental behavior. We researched the history of environmental communication in the U.S., current environmental-human health connections in water and air quality, and communication strategies that could encourage sustainability and support for parks in the County. This research culminated in a set of final recommendations for optimizing the pro-environmental messaging of the Department of Parks. Research into the history of environmental communication revealed wide variety of message types to gain support for sustainable behavior. Since the 1950s, messages catering to human values—altruistic or egoistic—and messages in line with social and media norms, have been prevalent. We believe that such messages could be used by the Department of Parks to promote park visitation and support. The investigation of environmental-human health connections revealed water and air quality deterioration as strong forces that are affecting both environmental and human health. Such forces, ranging from lead poisoning in water to carbon emissions in air, were found to be detrimental to both environments and humans, thus connecting the two—when environments are damaged, human health is damaged as well. However, parks can help mitigate these forces in a variety of ways. Finally, the most effective forms of communication are those that are simple; messages that are straightforward and easy to understand by varied audiences. Furthermore, we found that messages that encourage environmental-human health protection were most effective when crafted as a social norm or human value, not by using information alone. Based on of these findings, we devised a set of recommendations for Department of Parks messaging that include four steps that should be used in crafting Department messages: begin with an introductory hook; describe environmental-human health connections; craft environmental-human health connections; conclude with a call to action. We hope that these steps will help the Department garner optimal public support for its parks and natural environment.