The author presents a survey of the –iexperimental–n inquiries in the field indicated, regarding the general method of experiment in this field as involving "in essence a comparison between measured achievements of the individual person when under influences from other persons physically present with the measured achievements (in identical functions) of the same individual when working alone." The studies considered deal with the effect upon the individual's performance (work, judgment, opinion, report) of spectators or auditors, co-workers, competition, social encouragement and discouragement, group discussion, inclusion (of report) in a social chain or series of reporters, majority opinion, and expert opinion. Bibliography. (PsycINFO Database Record (c) 2012 APA, all rights reserved)