The paper presents four studies on the structure of environmental attitudes, based on Stern & Dietz's (1994) value-basis theory, which suggests that environmental concerns are rooted in three value orientations: self, other people, and the biosphere. The studies used confirmatory factor analysis to test the three-factor model of environmental concerns. Study 1, with 1010 U.S. college students, confirmed the three-factor model, showing that concerns for self, others, and the biosphere loaded on separate but correlated factors. Study 2, with a sample of 1005 U.S. adults, also supported the three-factor model, with similar results to Study 1. Study 3 examined the relationship between environmental concerns, environmental attitudes, empathy, and social-value orientation, finding that biospheric concerns were positively correlated with empathy and self-reported proenvironmental behavior. Study 4, involving 10 countries, confirmed the three-factor model across diverse samples, showing that biospheric concerns were positively correlated with self-transcendence and negatively with self-enhancement. The results provide strong evidence for the distinction between egoistic, altruistic, and biospheric environmental concerns. The findings suggest that environmental concerns are influenced by an individual's values and perceptions of the interconnection between self and nature. The studies collectively support the value-basis theory, indicating that environmental concerns are shaped by the relative importance individuals place on self, others, and the biosphere.The paper presents four studies on the structure of environmental attitudes, based on Stern & Dietz's (1994) value-basis theory, which suggests that environmental concerns are rooted in three value orientations: self, other people, and the biosphere. The studies used confirmatory factor analysis to test the three-factor model of environmental concerns. Study 1, with 1010 U.S. college students, confirmed the three-factor model, showing that concerns for self, others, and the biosphere loaded on separate but correlated factors. Study 2, with a sample of 1005 U.S. adults, also supported the three-factor model, with similar results to Study 1. Study 3 examined the relationship between environmental concerns, environmental attitudes, empathy, and social-value orientation, finding that biospheric concerns were positively correlated with empathy and self-reported proenvironmental behavior. Study 4, involving 10 countries, confirmed the three-factor model across diverse samples, showing that biospheric concerns were positively correlated with self-transcendence and negatively with self-enhancement. The results provide strong evidence for the distinction between egoistic, altruistic, and biospheric environmental concerns. The findings suggest that environmental concerns are influenced by an individual's values and perceptions of the interconnection between self and nature. The studies collectively support the value-basis theory, indicating that environmental concerns are shaped by the relative importance individuals place on self, others, and the biosphere.