Keyes ( 2005 Keyes, CLM . 2005. Mental illness and/or mental health? Investigating the axioms of the complete state model of health. Journal of Consulting and Clinical Psychology, 73: 539–548. [Crossref], [PubMed], [Web of Science ®] [Google Scholar] ) operationalized flourishing as elevated emotional, psychological, and social well-being. The current study predicted that flourishing among undergraduate students (N = 397) would have adaptive cognitive and behavioral achievement-related correlates. Results showed that students classified as flourishing (21.4% of the sample), relative to those classified as moderately mentally healthy (59.4%) or as languishing (19.1%), were less likely to adopt an entity view of ability or to procrastinate and were more likely to endorse mastery-approach goals, to report high self-control, and to report high grades. Results are cast in terms of possible accounts of the relationship between well-being and achievement-related functioning.