Part I. The Research Agenda 1. What Is Ecological Rationality? Peter M. Todd and Gerd Gigerenzer Part II. Uncertainty in the World 2. How Heuristics Handle Uncertainty Henry Brighton and Gerd Gigerenzer 3. When Simple Is Hard to Accept Robin M. Hogarth 4. Rethinking Cognitive Biases as Environmental Consequences Gerd Gigerenzer, Klaus Fiedler, and Henrik Olsson Part III. Correlations Between Recognition and the World 5. When is the Recognition Heuristic an Adaptive Tool? Thorsten Pachur, Peter M. Todd, Gerd Gigerenzer, Lael J. Schooler, and Daniel G. Goldstein 6. How Smart Forgetting Helps Heuristic Inference Lael J. Schooler, Ralph Hertwig, and Stefan M. Herzog 7. How Groups Use Partial Ignorance to Make Good Decisions Konstantinos V. Katsikopoulos and Torsten Reimer Part IV. Redundancy and Variability in the World 8. Redundancy: Environment Structure That Simple Heuristics Can Exploit Jorg Rieskamp and Anja Dieckmann 9. The Quest for Take-The-Best: Insights and Outlooks from Experimental Research Arndt Broder 10. Efficient Cognition Through Limited Search Gerd Gigerenzer, Anja Dieckmann, and Wolfgang Gaissmaier 11. Simple Rules for Ordering Cues in One-Reason Decision Making Anja Dieckmann and Peter M. Todd Part V. Rarity and Skewness in the World 12. Why Rare Things Are Precious: How Rarity Benefits Inference Craig R. M. McKenzie and Valerie M. Chase 13. Ecological Rationality for Teams and Committees: Heuristics in Group Decision Making Torsten Reimer and Ulrich Hoffrage 14. Naïve, Fast, and, Frugal Trees for Classification Laura F. Martignon, Konstantinos V. Katsikopoulos, and Jan K. Woike 15. How Estimation Can Benefit From an Imbalanced World Ralph Hertwig, Ulrich Hoffrage, and Rudiger Sparr Part VI. Designing the World 16. Designed to Fit Minds: Institutions and Ecological Rationality Will M. Bennis, Konstantinos V. Katsikopoulos, Daniel G. Goldstein, Anja Dieckmann, and Nathan Berg 17. Designing Risk Communication in Health Stephanie Kurzenhauser and Ulrich Hoffrage 18. Car Parking as a Game Between Simple Heuristics John M. C. Hutchinson, Carola Fanselow, and Peter M. Todd Part VII. Afterword 19. Ecological Rationality: The Normative Study of Heuristics Gerd Gigerenzer and Peter M. Todd