This special issue contains a selection of papers presented at the third Conference on Information Integration Theory and Functional Measurement held in San Diego, California, on August 8–9, 2011i . The studies reported in these papers largely rely on Information Integration Theory (IIT) and Functional Measurement (FM). For a comprehensive discussion of IIT and FM theory the reader is referred to Anderson’s books (1981, 1982, 1996, 2008). A condensed explanation of this theory can be found in the editorial of the 2009 conference (Hofmans, 2010). Although all contributions rely on IIT and FM, the 2011 conference was characterized by diversity: Contributions were from researchers from all over the world representing a wide diversity of nationalities; recent new procedures for identifying individual differences in integration rules and in scale values (Hofmans & Mullet, in press) have sparked renewed interest in the joint use of nomothetic and idiographic approaches by explicitly focusing on diversity while studying average patterns; and the reported applications were highly diverse most probably because the topics studied using IIT and FM keep expanding year after year. In what follows, we overview the papers presented in this issue. They can be categorized in the following broad categories of applied research topics: sports decision making, intuitive physics, equity and fairness, child development, attitude formation, trusting beliefs, quality of life, sleep, extreme settings, and methodological issues.