Global scientific research consistently demonstrates that human behavior has a direct impact on the health of the environment. Climate change, habitat loss and ocean acidification have all been linked to lifestyle choices such as a lack of recycling and overuse of plastics. Scientists and psychologists alike argue conservation efforts must center on changing human behavior. Psychological studies have shown that conservation education alone does not consistently lead to changes in behavior; psychological strategies are needed to increase behavioral changes. Despite the clear link between human behavior and environmental crises, psychological strategies aimed at promoting pro-environmental behavior are lacking in United States classrooms. Educational psychologist Howard Gardner's theory of multiple intelligences (MI) has been used to explain variations in human behavior, such as interest in natural phenomena. According to MI theory, the ability to connect with, understand and relate to nature is known as the "naturalistic intelligence." It has been proposed that a "high" naturalistic intelligence could predict engagement in pro-environmental behaviors. The present research analyzed the relationship between naturalistic intelligence scores and engagement in pro-environmental behaviors among young adults. Young adults are believed to be poised to inherit present environmental problems and are likely the key to achieving a sustainable future. A moderate, positive relationship between naturalistic intelligence and engagement in pro-environmental behavior was found. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]