 667
Why do people do what they do? Can psy -
chologists predict how a particular person 
will behave in a particular situation? Bet -
ter yet, can psychologists explain why  the 
person behaves that way in that situation? 
What people do depends on both who they 
are—their dispositions such as personality 
traits—  and the situation they are in. The 
obviousness of this statement only high -
lights how odd it is that psychologists man -
age to find ways of disagreeing with each 
other over its implications. As the decades- 
long “person–  situation debate” continues to 
prove (Donnellan, Lucas, & Fleeson, 2009; 
Fleeson & Furr, 2016; Funder, 2001; Ken -
rick & Funder, 1988), a surprising number 
of researchers appear to be both personally 
and professionally invested in believing that 
either situations or persons have stronger 
effects on behavior. By focusing on person– 
situation interaction, rather than person– 
situation competition, personality psycholo -
gy is moving beyond such disagreements and 
debate, toward a more complete understand -
ing of why people do what they do. The pur -
pose of this chapter is to present the idea of 
person–  situation interaction, its conceptual 
roots, and the ways in which it shapes con -
temporary personality research and theory.These issues are important because 
person–  situation interaction should be a key 
foundation for any personality theory that 
attempts to explain why a given person be -
haves in a given way in a given situation. Not 
all theories in personality psychology (or so -
cial psychology) are intended to be compre -
hensive in this way, and such theories might 
reasonably focus on concepts, processes, or 
phenomena that might not reflect person– 
situation interaction. However, person– 
situation interaction is an essential part of 
a broader understanding of why people do 
what they do.
By distilling and integrating contempo -
rary approaches to person–  situation inter -
action, we hope to direct readers’ attention 
to some of the most promising directions in 
personality psychology, and stimulate new 
ideas that advance understanding of person -
ality and its effects on behavior
Conceptual Roots of  Person–
Situation  Interactions
As a way of understanding “why do people 
do what they do?” and “how we explain why  
a person behaves in a certain way in a cer -CHAPTER 31
Persons, Situations,  
and Person–Situation Interactions
R. Michael Furr  
David  C. Funder