Although many psychologists have expressed an interest in the phenomenon of creativity, psychological research on this topic did not rapidly expand until after J. P. Guilford claimed, in his 1950 APA presidential address, that this topic deserved far more attention than it was then receiving. This article reviews the progress psychologists have made in understanding creativity since Guilford's call to arms. Research progress has taken place on 4 fronts: the cognitive processes involved in the creative act, the distinctive characteristics of the creative person, the development and manifestation of creativity across the individual life span, and the social environments most strongly associated with creative activity. Although some important questions remain unanswered, psychologists now know more than ever before about how individuals achieve this special and significant form of optimal human functioning.