Dr. Gigerenzer is one of the leading researchers in the field of human decision making. His research tries to find the mechanisms by which humans make decisions in real-world situations. Unlike many other models, Dr. Gigerenzer's approach assumes that much of the relevant information is not known to an individual, that it is unclear what the probabilities of certain events are, what the consequences of a decision are, etc. This sets his research program apart from those approaches which try to model optimal human decision making behavior in so-called 'small worlds' - in which all of the important information is known to the decision maker. In his work, Dr. Gigerenzer has focuse on the role of fast and frugal heuristics that can drive good decision making without taking up too many resources of the decision maker. In addition, his group at the Max Planck Institute for Human Development looks at how efficient decision strategies have emerged through evolution and under what conditions a particular decision making strategy or heuristic is 'ecologically rational'.