A group of 31 men interested in the new field of psychology established the American Psychological Association in 1892. The APA experienced rapid growth in membership as the popularity of psychology as a profession increased and in 2010 includes 148,000 members.
In 1928, the U.S. National Research Council sponsored a conference to set stylistic standards for the publication of manuscripts in anthropological and psychological journals. Editors and managers of prominent journals, as well as noted psychologists and anthropologists, attended the conference, which was chaired by American psychologist Madison Bentley.
The conference released its recommendations in a seven-page article that appeared in the February 1929 edition of “Psychological Bulletin,” a journal published by the APA. The APA itself adopted these recommendations as its own official style manual, requiring that everyone writing for its publications utilize it. At the time, the guide focused solely on stylistic issues.
Over the following decades, the APA revised its style manual until it finally released its revisions in the first edition of the "Publication Manual of the American Psychological Association" in 1952. "Psychological Bulletin" published this expanded, 60-page edition as a supplement to its regular issue.
The APA revised and published a second edition in 1974. The association published this edition separate from its "Psychological Bulletin" publication and greatly expanded its contents to a length of 136 pages. The third edition followed in 1983, with the APA releasing the fourth and fifth editions in 1994 and 2001, respectively.
Beginning with the second edition, the APA began publishing the manual with a wider audience in mind, as many university undergraduate and graduate programs in psychology and related disciplines adopted the first edition as their own departmental style guide.
Whereas early editions focused solely on stylistic concerns, modern editions have expanded their scope to include scholarly and ethical concerns relating to topics such as plagiarism and biased language.
The APA released the sixth edition of its style manual in 2009. Major changes relate primarily to the way in which electronic resources are cited and utilized. While the first printing of the sixth edition included errors in the presentation of some APA style rules, subsequent editions were corrected.