**Study 1 Procedure** After consent, participants took measures of implicit and explicit identification with environmentalists, followed by measures of environmental behaviors, concern, and policy support. Then, they were debriefed. **Study 1 Materials (For a demonstration, click this [link][1])** We adapted Bluemke and Friese's (2007) ST-IAT procedure for the current study. This adapted ST-IAT consisted of five blocks (20 trials in the first block, 48 trials in other blocks). Participants in the first block sorted words belonging to one of two categories (Self and Other) by pressing either "E" (for Other) or "I" for (for Self). In the second block, participants sorted words belonging to one of three categories (Self, Other, and Environmentalist) by pressing either "E" (for Other) or "I" for (for Self or Environmentalist). In the third block, participants did the same except Environmentalist words are also categorized with Other-related words instead of Self-related words. The fourth block is the same as the second block, and the fifth block is the same as the third block. Each block had 20 trials for the attribute that Environmentalist is not paired with, 14 trials for Environmentalist, and 14 trials for the attribute that Environmentalist is paired with. There was no response deadline, no feedback for correct responses, and participants were required to correct incorrect responses. Participants were randomly assigned to take the ST-IAT in the order above or in a flipped order where Other/Environmentalist vs. Self are Blocks 2 and 4 and Other vs. Self/Environmentalist are Blocks 3 and 5. The ST-IAT will be scored with the IAT D2 algorithm (Greenwald et al., 2003). The stimuli for each category are below: Environmentalist: Environmentalist, Conservationist, Preservationist, Tree-Hugger Self: Mine, Myself, Self, I, My Other: They, Their, Them, Theirs, Other Environmentalist identification, 1 (Disagree strongly) to 7 (Agree strongly).Adapted from Smith et al. (2007). 1. I see myself as an environmentalist. 2. I am pleased to be an environmentalist 3. I feel strong ties with environmentalists 4. I identity with other environmentalists. Environmental behaviors, 1-5: Never, Rarely, Sometimes, Often, Always (these six items have the highest loadings on the first factor using PCA in a previous study for the 21 item scale) “Now, please respond to these questions about your behavior. Don't feel any pressure, just indicate what you choose to do.” 1. When you visit the grocery store, how often do you use reusable bags? 2. How often do you conserve water when showering, cleaning clothes, washing dishes, watering plants, or during other activities? 3. How often do you discuss environmental topics, either in person or with online posts (Facebook, Twitter, etc.)? 4. When you buy clothing, how often is it from environmentally friendly brands? 5. How often do you engage in political action or activism related to protecting the environment? 6. How often do you educate yourself about the environment? Environmental concern. Five items from the New Ecological Paradigm scale were included (NEP; Dunlap, 2005; five-item subset used by Stern, 1999). 1 (Disagree strongly) to 7 (Agree strongly). 1. The so-called “ecological crisis” facing humankind has been greatly exaggerated. (R) 2. The earth is like a spaceship with limited room and resources. 3. If things continue on their present course, we will soon experience a major ecological catastrophe. 4. The balance of nature is strong enough to cope with the impacts of modern industrial nations. (R) 5. Humans are severely abusing the environment. Political opinion. Novel. 1 (Disagree strongly) to 7 (Agree strongly). 1. The United States should implement cap-and-trade or a carbon tax to reduce greenhouse gas emissions. 2. The United States should approve the Keystone XL pipeline that would carry crude oil from the Alberta tar sands. Demographics & political orientation are included with Project Implicit. [1]: https://dw2.psyc.virginia.edu/implicit/Launch?study=/user/calvin/sustain1/sustain1.expt.xml&refresh=true