In 1950 a group of citizens of New York City, working with limited and unpaid professional assistance, organized and carried out a campaign to reduce discrimination in restaurants in an area around the United Nations building. The event is of interest to social science because the group evaluated its success by a systematic comparison of restaurant practices before and after the campaign. While a number of communities have undertaken "self-surveys" of discriminatory practices, this is the only case known to the writer in which the results of the undertaking have been objectively measured.