Psychology at the beginning of the twenty-first century has
become a highly diverse field of scientific study and applied
technology. Psychologists commonly regard their discipline
as the science of behavior, and the American Psychological
Association has formally designated 2000 to 2010 as the
“Decade of Behavior.” The pursuits of behavioral scientists
range from the natural sciences to the social sciences and embrace
a wide variety of objects of investigation. Some psychologists
havemorein common with biologists than with
most other psychologists, and somehavemorein common
with sociologists than with most of their psychological colleagues.
Some psychologists are interested primarily in the behavior
of animals, some in the behavior of people, and others
in the behavior of organizations. These and other dimensions
of difference among psychological scientists are matched by
equal if not greater heterogeneity among psychological practitioners,
who currently apply a vast array of methods in many
different settings to achieve highly varied purposes.